Lens and eyewear

ABSTRACT

A lens that includes an electroactive region where an optical characteristic changes by electric control comprises: a transparent substrate; a second transparent substrate disposed facing the first transparent substrate; and an intermediate layer disposed between the first transparent substrate and the second transparent substrate; and including a mark including information.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a continuation of application Ser. No.16/474,196, filed on Jun. 27, 2019, which claims the benefit of priorityfrom Japanese Patent Application No. 2016-253581, filed on Dec. 27,2016, Japanese Patent Application No. 2016-253582, filed on Dec. 27,2016, and Japanese Patent Application No. 2017-037313, filed on Dec. 28,2016, the disclosure of which are incorporated herein in its entirety byreference.

TECHNICAL FIELD

The present invention relates to a lens and eyewear.

BACKGROUND ART

Patent Literature (hereinafter, abbreviated as PTL) 1 and PTL 2 discloselenses of eyewear. In each of these lenses, a focal length of a part ofregion can be changed with respect to a focal length of the other regionbased on energization of an internal electrode provided in the lens.This enables a user of eyewear provided with such a lens as describedabove to favorably view a thing disposed near the user through the abovepart of the region (that is, in a magnified view).

CITATION LIST Patent Literature

PTL 1

-   Japanese Unexamined Patent Application Publication (Translation of    PCT Application) No. 2011-516927    PTL 2-   Japanese Patent Application Laid-Open No. 2016-126145

SUMMARY OF INVENTION Technical Problem

Meanwhile, for attaching the lens as described above to a frame of theeyewear, it is desirable that the lens can be easily attached to theframe in a state where the internal electrode and the external electrodeof the lens are arranged so as to be stably connectable to each other ina direct or indirect manner.

An object of the present invention is to provide a lens that is easilyattachable to a frame, and eyewear having the lens.

Solution to Problem

A lens according to the present invention includes: a lens body; and aninternal electrode that is attached to the lens body, at least a part ofthe internal electrode being exposed in an outer edge part of the lensbody, in which a shape of a first region including an exposed part wherethe internal electrode is exposed and a shape of a second region notincluding the exposed part are different in the outer edge part of thelens body.

Advantageous Effects of Invention

The lens according to the present invention has an excellent effect thatthe lens is easily attachable to the frame. Further, the eyewearaccording to the present invention has an excellent effect that the lensis easily attachable to the frame.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an exploded perspective view illustrating exploded electronicglasses of Embodiment 1 according to the present invention;

FIG. 2 is a front view illustrating the electronic glasses of Embodiment1 according to the present invention;

FIG. 3 is a perspective view illustrating a flexible cable andconductive rubber;

FIG. 4 is a front view illustrating a lens having been cut out of a lensblank;

FIG. 5 is a front view illustrating the lens;

FIG. 6 is a sectional view along a line A-A of FIG. 5 ;

FIG. 7 is a sectional view along a line B-B of FIG. 5 ;

FIG. 8 is a sectional view illustrating Modification 1 of a secondfitting part of the lens and corresponding to FIG. 7 ;

FIG. 9 is a sectional view illustrating Modification 1 of a firstfitting part of the lens and corresponding to FIG. 6 ;

FIG. 10 is a sectional view illustrating Modification 2 of the firstfitting part of the lens and corresponding to FIG. 6 ;

FIG. 11 is a front view of electronic glasses of Embodiment 2 accordingto the present invention;

FIG. 12A is a sectional schematic view of a second fitting partaccording to Embodiment 2;

FIG. 12B is a sectional schematic view of Modification 1 of the secondfitting part according to Embodiment 2;

FIG. 12C is a sectional schematic view of Modification 2 of the secondfitting part according to Embodiment 2;

FIG. 12D is a sectional schematic view of Modification 3 of the secondfitting part according to Embodiment 2;

FIG. 12E is a sectional schematic view of Modification 4 of the secondfitting part according to Embodiment 2;

FIG. 13 is an exploded perspective view illustrating exploded electronicglasses of Embodiment 3 according to the present invention;

FIG. 14 is a front view illustrating the electronic glasses ofEmbodiment 3 according to the present invention;

FIG. 15 is a front view illustrating a lens and a lens blank accordingto Embodiment 3;

FIG. 16 is an explanatory diagram for explaining a line of sight of auser wearing the electronic glasses;

FIG. 17 is a front view illustrating a lens and a lens blank accordingto Modification 1 of Embodiment 3;

FIG. 18 is a front view illustrating a lens blank of a lens according toModification 2 of Embodiment 3;

FIG. 19 is a perspective view illustrating an example of a configurationof electronic glasses according to Embodiment 4 of the presentinvention;

FIG. 20 is a block diagram illustrating an internal circuit of theelectronic glasses according to Embodiment 4 of the present invention;

FIG. 21 is a sectional schematic view schematically illustrating anexample of a configuration of a lens;

FIG. 22A is an assembly diagram illustrating an example of aconfiguration of a part of the lens;

FIG. 22B is an assembly diagram seen from the opposite direction to FIG.22A;

FIG. 23 is a planar view illustrating an example of a configuration of alens blank;

FIG. 24A is a planar view illustrating an example of a configuration ofa lens blank according to Modification 1 of Embodiment 4;

FIG. 24B is a planar view illustrating an example of a configuration ofa lens blank according to Modification 2 of Embodiment 4;

FIG. 24C is a planar view illustrating an example of a configuration ofa lens blank according to Modification 3 of Embodiment 4; and

FIG. 24D is a planar view illustrating an example of a configuration ofa lens blank according to Modification 4 of Embodiment 4.

DESCRIPTION OF EMBODIMENTS Embodiment 1

Electronic glasses as eyewear according to Embodiment 1 of the presentinvention will be described with reference to FIGS. 1 to 7 . Note thatarrow FR appropriately illustrated in each drawing denotes the frontside seen from a user wearing electronic glasses 10, arrow UP denotesthe upper side, arrow RH denotes the right side, and arrow LH denotesthe left side. Further, when front-rear, vertical, and lateraldirections are used in the following description without beingspecified, those indicate front-rear, vertical, and lateral directionsseen from the user of the electronic glasses.

In the following description of lenses 12, 14 and each memberconstituting lenses 12, 14, a “thickness direction” corresponds to thefront-rear direction of electronic glasses 10, and a “width direction”corresponds to the lateral direction of electronic glasses 10. Moreover,when a “normal direction” is simply mentioned, this means a normaldirection for an external shape of each of lenses 12, 14 (see a solidline β of FIG. 5 ) in a planar view from the front-rear direction (thestate illustrated in FIG. 5 ). One side in the normal direction is adirection away from the center part of each of lenses 12, 14. Meanwhile,the other side in the normal direction is a direction closer to thecenter part of each of lenses 12, 14.

In the following embodiments, glasses will be illustrated as an exampleof the eyewear, but the eyewear is not limited thereto. The presentinvention may only be eyewear to be worn on or near the head, ears, oreyes of the user. The eyewear includes so-called glasses (includingelectronic glasses) having an auxiliary mechanism to improve theeyesight of the user, such as lenses, and various devices (for example,a glasses-type wearable terminal, a head-mounted display, and the like)having a mechanism to present information to the field of view, or theeyes, of the user.

As illustrated in FIGS. 1 and 2 , in electronic glasses 10 of thepresent embodiment, a focal length (power) of a part of each of left andright lenses 12, 14 can be changed by a switching operation of the user.Specifically, electronic glasses 10 are provided with frame 16 to beworn by the user, a pair of left and right lenses 12, 14 held in frame16, and liquid crystal driver 20 that drives liquid crystal 18 providedin lenses 12, 14.

Frame 16 has right-side rim 22, left-side rim 24, and bridge 26.Right-side rim 22 and left-side rim 24 hold right-side lens 14 andleft-side lens 12, respectively. Right-side rim 22 and left-side rim 24each have an annular shape in a front view (seen from the front side ofthe user of electronic glasses 10).

Bridge 26 links between right-side rim 22 and left-side rim 24 in thelateral direction. Frame 16 has pad parts 28, to be fitted onto the noseof the user, in portions of right-side rim 22 and left-side rim 24, theportions being adjacent to bridge 26.

Frame 16 is provided with right-side temple 30 (also referred to astemple) attached to a right-side end part of right-side rim 22 so as tobe movable in an inclined manner, and left-side temple 32 (also referredto as temple) attached to a left-side end part of left-side rim 24 so asto be movable in an inclined manner.

As illustrated in FIG. 1 , right-side temple 30 has right-side templebody 34 and lid part 38. Right-side temple body 34 has groove part 36with the user side (also referred to as the inner side in the widthdirection) opened. Lid part 38 is attached to right-side temple body 34to close groove part 36. Note that right-side temple 30 and left-sidetemple 32 are fitted onto the head and the right and left ears of theuser when the user puts on electronic glasses 10.

Liquid crystal driver 20 changes the arrangement of liquid crystal 18provided in each of lenses 12, 14 described later. Liquid crystal driver20 has control module 40, flexible cable 42, battery 44, and switch 46.Each of flexible cable 42, battery 44, and switch 46 is connected tocontrol module 40.

Control module 40 is disposed in groove part 36 of right-side templebody 34. Control module 40 is not exposed to the user side in a statewhere lid part 38 is attached to right-side temple body 34. Switch 46 isfixed to the opposite side of right-side temple body 34 from the user(the outer side in the width direction, and the opposite side to theside where groove part 36 is formed).

Note that switch 46 of the present embodiment is a capacitive touchswitch that is operable by the user's touch. Battery 44 is removablyattached to a rear end part of right-side temple 30.

As illustrated in FIGS. 1 and 3 , flexible cable 42 is provided fromcontrol module 40, disposed in right-side temple 30, extending to anupper-side portion of right-side rim 22, bridge 26, and upper-sideportion of left-side rim 24.

Then, right-side lens 14 and left-side lens 12 are fixed to (mountedinto) right-side rim 22 and left-side rim 24, respectively. In thisstate, flexible cable 42 and internal electrodes 48, 50 (see FIG. 4 )are electrically connected through conductive rubber 72. Conductiverubber 72 is made of a conductive material and has viscoelasticity.

Note that conductive rubber 72 constitutes a part of flexible cable 42.Inside lens 12, a pair of conductive films (not illustrated) arearranged so as to sandwich liquid crystal 18 therebetween in thedirection of arrow FR.

Internal electrodes 48, 50 are electrically connected to one and theother of the pair of conductive films, respectively. When a voltage isapplied to internal electrodes 48, 50, the voltage is applied across thepair of conductive films. The orientation of liquid crystal 18 iscontrolled by an electric field generated due to the application of thevoltage across the conductive films. For example, when cholestericliquid crystal is employed as liquid crystal 18, a refractive index ofliquid crystal 18 is controlled by controlling the voltage acrossinternal electrodes 48 and 50.

Next, lenses 12, 14 being main parts of the present embodiment will bedescribed. Note that right-side lens 14 and left-side lens 12 are formedto be symmetrical. Therefore, in the following, left-side lens 12 willbe described, and for each part of right-side lens 14, the same numeralas that of left-side lens 12 will be provided and the description ofright-side lens 14 will be omitted.

As illustrated in FIG. 4 , lens 12 is obtained by processing lens blank52, having a circular outer edge in a front view, into a predeterminedshape.

As illustrated in FIG. 4 , lens blank 52 is provided with blank body 58having front lens 54 and diffraction-section including lens 56superimposed and joined in the thickness direction. Each of front lens54 and diffraction-section including lens 56 is gently curved so as toform a shape protruding forward.

In addition, front lens 54 and a portion of diffraction-sectionincluding lens 56, the portion excluding a portion provided withdiffraction section 60 described later, are joined via an adhesivelayer, not illustrated. Note that internal electrodes 48, 50 describedabove are buried in this adhesive layer.

A part of diffraction-section including lens 56 has diffraction section60 as a Fresnel lens part. Diffraction section 60 has a configuration ofa so-called Fresnel lens that has a saw-blade shape in a cross sectionon the front lens 54 side (front side).

Liquid crystal 18 is intervened between diffraction section 60 ofdiffraction-section including lens 56 and front lens 54. In liquidcrystal 18 (also referred to as refractive-index changing layer), therefractive index changes due to generation of the electric field byapplication of the voltage.

As illustrated in FIG. 5 , lens 12 is formed by processing lens blank 52into a shape corresponding to the shape of left-side rim 24 (see FIG. 1). Note that the configuration of lens body 68 of lens 12 corresponds tothe configuration of blank body 58 of lens blank 52.

In lens 12 of the present embodiment, shapes of portions to be fittedinto left-side rim 24 (that is, the shapes of the outer edge part) aredifferent from each other, the shapes being separated by a dashed-dottedline L illustrated in FIG. 5 as the boundary.

In lens 12, the portion fitted into left-side rim 24 above dashed-dottedline L is first fitting part 74 (also referred to as first region).Meanwhile, in lens 12, the portion fitted into left-side rim 24 belowdashed-dotted line L is second fitting part 76 (also referred to assecond region). That is, dashed-dotted line L indicates the boundaryposition between first fitting part 74 and second fitting part 76.

FIG. 6 illustrates a cross section of first fitting part 74 (a crosssection of a portion provided with internal electrode 48) in a casewhere lens body 68 is cut along its thickness direction (in other words,along a virtual plane parallel to the normal direction and the thicknessdirection).

As illustrated in FIG. 6 , first fitting part 74 has, at the center partin the thickness direction of lens body 68 (the lateral direction inFIG. 6 ), protruding part 78 (also referred to as exposed part)protruding in a direction orthogonal to the thickness direction of lensbody 68 and a direction away from lens body 68 (a direction of arrow α).

In other words, the center part of first fitting part 74 in thethickness direction protrudes to one side in the normal direction morethan both end parts (the right end part and the left end part in FIG. 6) of first fitting part 74 in the thickness direction. Specifically,first fitting part 74 has, at the center part in the thicknessdirection, protruding part 78 protruding to one side in the normaldirection.

Note that protruding part 78 is formed by providing a pair of step parts80 in a front-side portion and a rear-side portion on the outerperiphery of lens body 68. In other words, protruding part 78 is formedby setting the thickness dimension of the outer periphery of lens body68 to be smaller than the thickness dimension of the center portion oflens body 68.

Protruding part 78 continues over the whole length of first fitting part74 along the outer edge of lens body 68 (the external shape of lens body68 in a planar view from the front-rear direction). However, protrudingpart 78 may have a discontinuous portion in first fitting part 74.

Further, tip surface 78A of protruding part 78 in the protrudingdirection has a planar shape. The end part of internal electrode 48 isexposed on tip surface 78A. Note that in a portion provided in internalelectrode 50 (see FIG. 5 ) in first fitting part 74 as well, the endpart of internal electrode 50 is exposed on tip surface 78A ofprotruding part 78. Tip surface 78A does not need to be a perfect plane,but may have a substantially flat shape.

FIG. 7 illustrates a cross section of second fitting part 76 in a casewhere lens body 68 is cut along its thickness direction (in other words,along a virtual plane parallel to the normal direction and the thicknessdirection). As illustrated in FIG. 7 , second fitting part 76 graduallybecomes narrower as going in the direction orthogonal to the thicknessdirection of lens body 68 and the direction away from lens body 68 (adirection of arrow α).

In other words, second fitting part 76 becomes smaller in size (that is,narrower) in the thickness direction as going to one side in the normaldirection (downward in FIG. 7 ). Second fitting part 76 is therebyformed into a V-groove shape.

Note that an inclined surface being the front surface of second fittingpart 76 is referred to as front-side inclined surface 76A. Meanwhile, aninclined surface being the rear surface of second fitting part 76 isreferred to as rear-side inclined surface 76B. Here, “groove” is aportion formed by processing the outer periphery of lens body 68 so thatlenses 12, 14 are attached to frame 16 of the eyewear (electronicglasses 10 in the present embodiment).

The “V-groove shape” is a groove having a V-shaped tip shape. While theV-shaped tip shape can also be referred to as a tip shape with an acuteangle, the shape may not necessarily have a perfect acute angle, but mayonly be a shape with an angle close to an acute angle. The V-shaped tipshape may be a tapering or triangular tip shape.

As described above, in the case of the present embodiment, first fittingpart 74 and second fitting part 76 are different in the cross-sectionalshape when cut along the virtual plane parallel to the normal directionand the thickness direction (that is, the shapes illustrated in FIGS. 6and 7 ). In other words, first fitting part 74 and second fitting part76 are different in the external shape in the cross-sectional shapedescribed above. Note that the external shape may include the externalshape of internal electrode 48 exposed externally from first fittingpart 74.

As illustrated in FIGS. 6 and 7 , each of first fitting part 74 andsecond fitting part 76 is fitted into fitting groove 82 formed on theinner periphery of left-side rim 24. In fitting groove 82 of left-siderim 24, a portion to which first fitting part 74 is fitted has a shapecorresponding to the shape of first fitting part 74. Further, in fittinggroove 82, a portion to which second fitting part 76 is fitted has ashape corresponding to the shape of second fitting part 76.

In the case of the present embodiment, with lens 12 held in left-siderim 24, dashed-dotted line L (see FIG. 5 ) being the boundary betweenfirst fitting part 74 and second fitting part 76 is disposed belowbridge 26 or right-side temple 30 and left-side temple 32 (see FIG. 2 ).In other words, in the case of the present embodiment, second fittingpart 76 formed in the V-groove shape is not disposed in the portionfacing flexible cable 42.

That is, on the outer periphery of lens 12, at least the region on theupper side of the lens where the end parts of internal electrodes 48, 50are exposed has protruding part 78. Among the upper side and the rightand left sides of the lens, the region located above bridge 26 orright-side temple 30 and left-side temple 32 preferably has protrudingpart 78.

Meanwhile, on the outer periphery of lens 12, at least the region on thelower side of the lens has the V-groove shape. Among the lower side andthe right and left sides of the lens, the region located below bridge 26or right-side temple 30 and left-side temple 32 preferably has theV-groove shape.

As illustrated in FIG. 6 , first fitting part 74 may at least haveprotruding part 78 with tip surface 78A in substantially planar shapeand step parts 80 provided on each of the front-side portion and therear-side portion of protruding part 78.

Hence the side surface of protruding part 78 that connects between tipsurface 78A and step part 80 is not limited to the plane as illustrated,but may be a curved surface. An angle of contact between the sidesurface of protruding part 78 and tip surface 78A and an angle ofcontact between the side surface of protruding part 78 and step part 80may not necessarily be a right angle. In addition, protruding part 78can be expressed as a rectangular shape.

On the outer periphery of lens 12, at least the region including theregion where the end parts of internal electrodes 48, 50 are exposed hasprotruding part 78 as illustrated in FIG. 6 . Each of the end parts ofinternal electrodes 48, 50 are exposed on tip surface 78A having theplanar shape in protruding part 78. Meanwhile, the region where the endparts of internal electrodes 48, 50 are not exposed has the V-grooveshape as illustrated in FIG. 7 .

With such a configuration, in the region where the end parts of internalelectrodes 48, 50 are exposed, the end parts of internal electrodes 48,50 are exposed in the region in a substantially planar shape (that is,tip surface 78A) on the outer periphery of lens 12. As a result, thecontactability with the external electrode (flexible cable 42) in theregion is improved. Meanwhile, the region where the end parts ofinternal electrodes 48, 50 are not exposed, with the outer periphery oflens 12 having the V-groove shape, electronic glasses 10 and the likeare easily incorporated into the frame.

That is, on the outer periphery of lens 12, at least the regionincluding the region where the end parts of internal electrodes 48, 50are exposed has a planar portion at least on the outer periphery.Meanwhile, the region where the end parts of internal electrodes 48, 50are not exposed has a portion in a sharp shape on the outer periphery.

In other words, on the outer periphery of lens 12, the planar region onthe outer periphery (specifically, the thickness of lens 12 on the outerperiphery) in the region where the end parts of internal electrodes 48,50 are exposed is larger than that in the region where the end parts ofinternal electrodes 48, 50 are not exposed.

In other words, on the outer periphery of lens 12, the planar region onthe outer periphery (specifically, the thickness of lens 12 on the outerperiphery) in the region where the end parts of internal electrodes 48,50 are not exposed is smaller than that in the region where the endparts of internal electrodes 48, 50 are exposed.

Action and Effect of Present Embodiment

Next, the action and effect of the present embodiment will be described.

The voltage is not applied to liquid crystal 18 in a state where theuser is wearing electronic glasses 10 illustrated in FIGS. 1 and 2 andnot operating switch 46. Here, the refractive index of liquid crystal 18in the state of no voltage being applied is substantially the same asthose of front lens 54 and diffraction-section including lens 56. Hencethe power of the portion provided with diffraction section 60 in each ofleft and right lenses 12, 14 is substantially the same as the power ofthe portion except for diffraction section 60 in each of left and rightlenses 12, 14.

When the voltage is applied to liquid crystal 18 in accordance with theoperation of switch 46 by the user of electronic glasses 10, thearrangement of liquid crystal 18 is changed and the refractive index ofliquid crystal 18 changes. Thereby, the power of the portion providedwith diffraction section 60 in each of left and right lenses 12, 14becomes higher than the power of the portion except for diffractionsection 60 in each of left and right lenses 12, 14. In other words, thefocal length of the portion provided with diffraction section 60 becomesshorter than the focal length of the portion except for diffractionsection 60 in each of left and right lenses 12, 14.

As illustrated in FIGS. 5 to 7 , in the case of electronic glasses 10 ofthe present embodiment, left-side lens 12 is attached to frame 16 byfitting of first fitting part 74 and second fitting part 76 of lens body68 into fitting groove 82 of left-side rim 24 in frame 16.

Further, right-side lens 14 (see FIG. 2 ) is also attached to frame 16by fitting of first fitting part 74 and second fitting part 76 of lensbody 68 into fitting groove 82 of right-side rim 22 in frame 16.

As illustrated in FIGS. 6 and 7 , in the present embodiment, the shapeof first fitting part 74 and the shape of second fitting part 76 aredifferent in lens body 68 of each of lenses 12, 14. That is, asillustrated in FIG. 6 , first fitting part 74 has a shape to stabilizethe state of contact between each of internal electrodes 48, 50 andconductive rubber 72.

Meanwhile, as illustrated in FIG. 7 , second fitting part 76 has a shapeto facilitate fitting into fitting groove 82 of each of the rims(right-side rim 22 and left-side rim 24) in frame 16. To be morespecific, as illustrated in FIG. 6 , tip surface 78A of protruding part78 in first fitting part 74 has a planar shape. Such a configurationenables stable contact between internal electrodes 48, 50 and conductiverubber 72 in the portions where internal electrodes 48, 50 are exposed.

Further, as illustrated in FIG. 7 , second fitting part 76 is fittedinto fitting groove 82 of each of the rims (right-side rim 22 andleft-side rim 24) by pushing and sliding front-side inclined surface 76Aor rear-side inclined surface 76B of second fitting part 76 on each ofthe rims (right-side rim 22 and left-side rim 24) of frame 16. Asdescribed above, according to the present embodiment, it is possible toattach lenses 12, 14 to frame 16 while ensuring the state of contactbetween each of internal electrodes 48, 50 and conductive rubber 72.

In the present embodiment, the contact pressure between each of the endparts of internal electrodes 48, 50 and conductive rubber 72 can be madehigh due to exposure of each of the end parts of internal electrodes 48,50 on tip surface 78A of protruding part 78. Such a configuration iseffective for preventing a failure in contact between each of the endparts of internal electrodes 48, 50 and conductive rubber 72.

In the present embodiment, second fitting part 76 is in the V-grooveshape having front-side inclined surface 76A and rear-side inclinedsurface 76B. With such a configuration, the operability in removinglenses 12, 14 from the rims (right-side rim 22 and left-side rim 24) offrame 16 can be made favorable.

In the present embodiment, second fitting part 76 having the V-grooveshape is not disposed facing flexible cable 42. Such a configuration iseffective for preventing flexible cable 42 from being damaged by the tipof second fitting part 76.

In the present embodiment, the example has been described where thepresent invention is applied to lenses 12, 14 that are attached to frame16 having the annular rims (right-side rim 22 and left-side rim 24).However, an application object of the present invention is not limitedthereto.

For example, as in Embodiment 2 described later, the present inventioncan also be applied to lenses 12, 14 that are attached to a frame havinga rim only for the upper part of each of lenses 12, 14. FIG. 8 is apartial sectional view of second fitting part 76 a, illustratingModification 1 of the second fitting part. Second fitting part 76 a haswire fitting groove 84 with a groove shape, into which wire 83 havingboth ends fixed to frame 16, is fitted. Note that wire 83 constitutes apart of frame 16.

In the present embodiment, the example has been described whereprotruding part 78 is formed in first fitting part 74 to increase thecontact pressure between each of the end parts of internal electrodes48, 50 and conductive rubber 72, but the present invention is notlimited thereto.

FIG. 9 is a partial sectional view of first fitting part 74 a,illustrating Modification 1 of the first fitting part. On the outerperiphery of lens 12, first fitting part 74 a has groove-shaped rubberplacement groove 86 (also referred to as exposed part) where conductiverubber 72 is to be disposed.

When such a configuration is employed, the contact pressure between eachof the end parts of internal electrodes 48, 50 and conductive rubber 72may be increased by setting conductive rubber 72 so as to be shrunk inrubber placement groove 86.

As illustrated in FIG. 6 , in the present embodiment, the example hasbeen described where protruding part 78 is formed in first fitting part74 by providing step parts 80 with the same height in the front-sideportion and the rear-side portion on the outer periphery of lens body68. However, the present invention is not limited thereto.

FIG. 10 is a partial sectional view of first fitting part 74 b,illustrating Modification 2 of the first fitting part. In the case offirst fitting part 74 b, height H1 of step part 80 formed in thefront-side portion on the outer periphery of lens body 68 is smallerthan height H2 of step part 80 formed in the rear-side portion.

With such a configuration, on the front-surface side in the upper partof lens body 68, a gap formed between the rims (right-side rim 22 andleft-side rim 24 of frame 16) can be made small. As an example,difference H3 between height H1 of step part 80 formed in the front-sideportion on the outer periphery of lens body 68 and height H2 of steppart 80 formed in the rear-side portion is approximately 0.2 mm.However, difference H3 may be larger than this.

Summary of Present Embodiment

The lens and the eyewear having the lens according Embodiment 1described above include the following aspects:

[First Aspect]

A first aspect of the lens according to Embodiment 1 above is providedwith: a lens body; and an internal electrode that is attached to thelens body, at least a part of the internal electrode being exposed in anouter edge part of the lens body. In the outer edge part of the lensbody, a shape of a first region including an exposed part where theinternal electrode is exposed and a shape of a second region notincluding the exposed part are different.

[Second Aspect]

A lens according to a second aspect is the lens according to the firstaspect, in which the shape of the first region has a plane at a tip, andan end part of the internal electrode is exposed on the plane.

According to the lens of the second aspect, the state of contact betweenthe external electrode and internal electrode can be made favorable.

[Third Aspect]

A lens according to a third aspect is the lens according to the firstaspect, in which the shape of the second region is sharp at a tip.

According to the lens of the third aspect, it is possible to facilitatefitting of the second region of the lens body into the frame.

[Fourth Aspect]

A lens according to a fourth aspect is the lens according to the firstaspect, in which the shape of the second region has a groove part at atip.

According to the lens of the fourth aspect, the groove part is formed atthe tip of the second region of the lens body, so that a wire is fittedinto the groove part.

[Fifth Aspect]

A lens according to a fifth aspect is the lens according to the firstaspect, in which a thickness of an end part of the lens body in thefirst region is larger than a thickness of an end part of the lens bodyin the second region as viewed in a cross section cut along a thicknessdirection of the lens body.

According to the lens of the fifth aspect, it is possible to easily fitthe second region of the lens body into the frame.

[Sixth Aspect]

A lens according to a sixth aspect is the lens according to the secondaspect, in which the first region has a protruding shape including theplane at the tip, and the shape of the second region is a V-shape.

According to the lens of the sixth aspect, it is possible to facilitatefitting of the second region of the lens body into the frame, whileensuring the state of contact between the external electrode and theinternal electrode in the first region of the lens body.

[Seventh Aspect]

A lens according to a seventh aspect is the lens according to any one ofthe first to sixth aspects, in which an outer edge part on an upper sideof the lens body is the first region, an outer edge part on a lower sideof the lens body is the second region, and a boundary between the firstregion and the second region is located on each of right and left sidesof the lens body.

According to the lens of the seventh aspect, the external electrode canbe disposed along the upper side of the lens body.

[Eighth Aspect]

A lens according to an eighth aspect is the lens according to theseventh aspect, in which the boundary between the first region and thesecond region is located below a bridge or a temple of a frame ofeyewear, with the lens body held in the frame.

According to the lens of the eighth aspect, the external electrode canbe disposed along the upper part of the frame.

[Ninth Aspect]

A lens according to a ninth aspect is the lens according to any one ofthe first to eighth aspects, in which the lens body is held in theframe, the internal electrode is buried in the lens body andelectrically in contact with an external electrode provided in theframe, the first region is a first fitting part that is fitted into theframe with the exposed part in contact with the external electrode, andthe second region is a second fitting part that is connected to thefirst region and fitted into the frame.

According to the lens of the ninth aspect, it is possible to facilitatefitting of the second region of the lens body into the frame, whileensuring the state of contact between the external electrode provided inthe frame and the internal electrode buried in the lens body in thefirst region of the lens body. That is, it is possible to easily fit thelens into the frame.

[Tenth Aspect]

A lens according to a tenth aspect is the lens according to the firstaspect, in which at least a thickness dimension of the exposed part inthe first region is different from a thickness dimension of a centerportion of the lens body as viewed in a cross section cut along athickness direction of the lens body.

According to the lens of the tenth aspect, the contact pressure betweenthe internal electrode and the external electrode can be made high.

[Eleventh Aspect]

A lens according to an eleventh aspect is the lens according to thetenth aspect, in which at least the thickness dimension of the exposedpart in the first region is set to be smaller than the thicknessdimension of the center portion of the lens body as viewed in a crosssection cut along the thickness direction of the lens body.

According to the lens of the eleventh aspect, the contact pressurebetween the internal electrode and the external electrode can be madehigh.

[Twelfth Aspect]

Eyewear according to a twelfth aspect is provided with: the lensaccording to any one of the first to eleventh aspects; a frame includinga lens holder by which the lens is held, the frame being a portion to beworn by a user; and an external electrode disposed between the lensholder and the lens.

According to the eyewear of the twelfth aspect, it is possible tofacilitate fitting of the second region of the lens body into the frame,while ensuring the state of contact between the internal electrode andthe external electrode in the first region of the lens body.

[Thirteenth Aspect]

Eyewear according to a thirteenth aspect is the eyewear according to thetwelfth aspect, in which a conductive rubber is disposed between theexposed part and the external electrode.

According to the eyewear of the thirteenth aspect, the internalelectrode and the external electrode provided in the lens body can beconnected via the conductive rubber.

While one embodiment of the present invention has been described above,the present invention is not limited to the configuration describedabove, but can naturally be performed in a configuration other than theconfiguration described above by being subjected to various modificationwithin a range not deviating from the gist of the invention.

Embodiment 2

Embodiment 2 according to the present invention will be described withreference to FIGS. 11 to 12E. Electronic glasses 10 a of the presentembodiment is different from electronic glasses 10 of Embodiment 1described above (see FIGS. 1 and 7 ) in configurations of frame 16 a,second fitting parts 76 b to 76 f in each of lenses 12 a, 14 a.

The other configurations of electronic glasses 10 a are similar to thosein Embodiment 1 described above. Therefore, in the following, electronicglasses 10 a according to the present embodiment will be described witha focus on the configurations different from those in Embodiment 1described above. In the present embodiment, for a similar configurationto that in Embodiment 1, the description of Embodiment 1 above can becited as appropriate.

In the case of the present embodiment, frame 16 a is a so-called halfrim type frame, having right-side rim 22 a, left-side rim 24 a,right-side wire 83 a, left-side wire 83 b, bridge 26, right-side temple30 (see FIG. 1 ), and left-side temple 32 (see FIG. 2 ). Theconfigurations of bridge 26, right-side temple 30, and left-side temple32 are similar to the case of Embodiment 1 described above.

Each of right-side rim 22 a (the right-side rim seen from a user ofelectronic glasses 10 a) and left-side rim 24 a has a partial annularshape in a front view (seen from the front side of the user ofelectronic glasses 10 a). That is, right-side rim 22 a (left-side rim 24a) holds a part of the outer periphery of lens 14 a (lens 12 a).

Specifically, right-side rim 22 a (left-side rim 24 a) holds a part ofthe outer periphery of lens 14 a (12 a) including either the upper parton the outer periphery of lens 14 a (12 a) (hereinafter simply referredto as outer peripheral upper part) or the lower part thereon(hereinafter simply referred to as outer peripheral lower part) (in thecase of FIG. 11 , including the outer peripheral upper part).

In the present embodiment, right-side rim 22 a and left-side rim 24 aare in a symmetrical relation, and hence a specific structure ofright-side rim 22 a will be described below. For left-side rim 24 a, thedescription of right-side rim 22 a can be cited as appropriate.

Right-side rim 22 a has upper rim element 200, first side rim element201, and second side rim element 202. Upper rim element 200 (alsoreferred to as first rim element) holds the outer peripheral upper partsof lenses 12 a, 14 a. Upper rim element 200 extends in the widthdirection (the lateral direction in FIG. 11 ) along the outer peripheralupper part of each of lenses 12 a, 14 a.

First side rim element 201 (also referred to as second rim element)holds an outer periphery of a portion of each of lenses 12 a, 14 a in afront view, the portion being on the outer side in the width direction(the lateral direction in FIG. 11 ) and closer to the upper end (alsoreferred to as first outer peripheral side part). First side rim element201 extends in the vertical direction (the vertical direction in FIG. 11) along the first outer peripheral side parts of lenses 12 a, 14 a.

One end of first side rim element 201 (the upper end in the case of thepresent embodiment) continues to the outer-side end part of upper rimelement 200 in the width direction. Meanwhile, one end of right-sidewire 83 a, described later, is fixed to the other end (the lower end inthe case of the present embodiment) of first side rim element 201.

Second side rim element 202 (also referred to as third rim element)holds an outer periphery of a portion of each of lenses 12 a, 14 a, theportion being on the inner side in the width direction and closer to theupper end (also referred to as second outer peripheral side part).Second side rim element 202 extends in the vertical direction (thevertical direction in FIG. 11 ) along the second outer peripheral sidepart of each of lenses 12 a, 14 a.

One end (the upper end in the case of the present embodiment) of secondside rim element 202 continues to the inner-side end part of upper rimelement 200 in the width direction. Meanwhile, the other end ofright-side wire 83 a, described later, is fixed to the other end (thelower end in the case of the present embodiment) of second side rimelement 202.

Right-side rim 22 a has fitting groove 82 (see FIG. 6 ) on the innersurface (the surface facing the outer periphery of lens 14 a). Theconfiguration of fitting groove 82 is similar to that in Embodiment 1described above.

Both ends of right-side wire 83 a are fixed to right-side rim 22 a.Specifically, one end (the left-side end part of FIG. 11 ) of right-sidewire 83 a is fixed to one end (the left-side end part of FIG. 11 ) ofright-side rim 22 a. In the case of the present embodiment, one end (theleft-side end part of FIG. 11 ) of right-side wire 83 a is fixed to theother end of first side rim element 201 of right-side rim 22 a.

Meanwhile, the other end (the right-side end part of FIG. 11 ) ofright-side wire 83 a is fixed to the other end (the right-side end partin FIG. 11 ) of right-side rim 22 a. In the case of the presentembodiment, the other end of right-side wire 83 a is fixed to the otherend of second side rim element 202 of right-side rim 22 a. Right-siderim 22 a and right-side wire 83 a are configured into an annular shapealong the external shape of lens 14 a in a planar view from thefront-rear direction. Since left-side wire 83 b is symmetrical toright-side wire 83 a, a specific description of left-side wire 83 b willbe omitted.

Next, a pair of left and right lenses 12 a, 14 a will be described. Thebasic structures of a pair of left and right lenses 12 a, 14 a aresimilar to those in Embodiment 1 described above. Further, sinceleft-side lens 12 a and right-side lens 14 a are symmetrical, right-sidelens 14 a will be described below.

In lens 14 a, at least the shape of outer periphery held by upper rimelement 200 is different from the shape of the outer periphery held byright-side wire 83 a. In the case of the present embodiment, in lens 14a, the shape of the outer periphery held by right-side rim 22 a (upperrim element 200, first side rim element 201, and second side rim element202) is different from the shape of the outer periphery held byright-side wire 83 a.

Specifically, lens 14 a has first fitting part 74 (also referred to asfirst region) in a portion held by right-side rim 22 a on the outerperiphery. First fitting part 74 is similar to that in Embodiment 1described above. Meanwhile, lens 14 a has second fitting part 76 b (alsoreferred to as second region) in a portion held by right-side wire 83 a(in other words, a portion not held by right-side rim 22 a) on the outerperiphery.

Second fitting part 76 b is similar to second fitting part 76 aillustrated in FIG. 8 .

Hereinafter, second fitting part 76 b according to the presentembodiment will be described with reference to FIG. 12A.

First, summaries of second fitting part 76 b illustrated in FIG. 12A,and second fitting parts 76 c to 76 f illustrated in FIGS. 12B to 12Ewhich are modifications of second fitting part 76 b will be described.

Any of second fitting parts 76 b to 76 f has a recess and a protrusionalternately arranged in the thickness direction in a cross-sectionalshape in the case of being cut along a virtual plane parallel to thenormal direction and the thickness direction. The number of each ofrecesses and protrusions may be one, or two or larger. The recessconstitutes each of wire fitting grooves 84 to 84 c and wire fittingnotch 87, described later. Meanwhile, the tip surface of the protrusionconstitutes each of protrusions 85 a to 85 c described later. Note thatthe tip surface of the protrusion is preferably a flat surface. However,the tip surface of the protrusion may be an inclined surface or a curvedsurface.

FIG. 12A is a sectional schematic view in a case where a portion of lens14 a where second fitting part 76 b is disposed is cut along a virtualplane parallel to the normal direction and the thickness direction.

Second fitting part 76 b has wire fitting groove 84 in an intermediatepart in the thickness direction (the lateral direction in FIG. 12A)which is recessed to the other side in the normal direction (upward inFIG. 12A) more than both end parts in the thickness direction. In thecase of the present embodiment, wire fitting groove 84 is provided atthe center of second fitting part 76 b in the thickness direction.

Wire fitting groove 84 has a rectangular cross-sectional shape when cutalong a virtual plane parallel to the normal direction and the thicknessdirection. Wire fitting groove 84 continues over the whole length ofsecond fitting part 76 b

Second fitting part 76 b has a pair of protrusions 85 a, 85 b, the tipsof which are flat surfaces, in positions sandwiching wire fitting groove84 from the front-rear direction. The pair of protrusions 85 a, 85 bcontinue over the whole length of second fitting part 76 b.

Right-side wire 83 a is fitted into wire fitting groove 84 of secondfitting part 76 b having such a configuration as above. Meanwhile, asillustrated in FIG. 6 , first fitting part 74 is fitted into fittinggroove 82 formed on the inner periphery of right-side rim 22 a. In thismanner, lens 14 a is held in right-side rim 22 a and right-side wire 83a.

Hereinafter, Modifications 1 to 4 of second fitting part 76 b accordingto Embodiment 2 will be described with reference to FIGS. 12B to 12E.

FIG. 12B is a sectional schematic view of Modification 1 of the secondfitting part. Second fitting part 76 c has wire fitting groove 84 a at aposition in an intermediate part in the thickness direction (the lateraldirection in FIG. 12B), the position being shifted from the center partto one side in the thickness direction (the left side in FIG. 12B). Wirefitting groove 84 a has a groove shape recessed to the other side in thenormal direction (upward in FIG. 12B).

Wire fitting groove 84 a has a rectangular cross-sectional shape whencut along a virtual plane parallel to the normal direction and thethickness direction. Note that second fitting part 76 c may have wirefitting groove 84 a at a position in an intermediate part in thethickness direction (the lateral direction in FIG. 12B), the positionbeing shifted from the center part to one side in the thicknessdirection (the right side in FIG. 12B).

Right-side wire 83 a or left-side wire 83 b is fitted into wire fittinggroove 84 a as described above. The other configuration of secondfitting part 76 c is similar to that of second fitting part 76 b inEmbodiment 2 above.

FIG. 12C is a sectional schematic view of Modification 2 of the secondfitting part. Second fitting part 76 d has wire fitting groove 84 b inan intermediate part (the center part in the case of the illustration)in the thickness direction (the lateral direction in FIG. 12C). Wirefitting groove 84 b has a groove shape recessed to the other side in thenormal direction (upward in FIG. 12C). Specifically, wire fitting groove84 b has a triangular cross-sectional shape when cut along a virtualplane parallel to the normal direction and the thickness direction.

In the above cross-sectional shape, wire fitting groove 84 b has asmaller dimension in the thickness direction (the lateral direction inFIG. 12C) as going away from an opening (as going upward in FIG. 12C).Right-side wire 83 a or left-side wire 83 b is fitted into wire fittinggroove 84 b as described above. The other configuration of secondfitting part 76 d is similar to that of second fitting part 76 b inEmbodiment 2 above.

FIG. 12D is a sectional schematic view of Modification 3 of the secondfitting part. Second fitting part 76 e has wire fitting groove 84 c inan intermediate part (the center part in the case of the illustration)in the thickness direction (the lateral direction in FIG. 12D). Wirefitting groove 84 c has a groove shape recessed to the other side in thenormal direction (upward in FIG. 12D). Specifically, wire fitting groove84 c has a semicircular cross-sectional shape when cut along a virtualplane parallel to the normal direction and the thickness direction. Notethat the cross-sectional shape of wire fitting groove 84 c is notlimited to a semicircle. The cross-sectional shape of wire fittinggroove 84 c may be formed using a curved line other than the semicircle.Alternatively, the cross-sectional shape of wire fitting groove 84 c maybe formed using a combination of curved and straight lines.

In the above cross-sectional shape, wire fitting groove 84 c has asmaller dimension in the thickness direction (the lateral direction inFIG. 12D) as going away from an opening (as going upward in FIG. 12D).Right-side wire 83 a or left-side wire 83 b is fitted into wire fittinggroove 84 c as described above. The other configuration of secondfitting part 76 e is similar to that of second fitting part 76 b inEmbodiment 2 above.

FIG. 12E is a sectional schematic view of Modification 4 of the secondfitting part. Second fitting part 76 f has wire fitting notch 87recessed to the other side in the normal direction (upward in FIG. 12E)more than one half part (a left-half part in FIG. 12E) in the other halfpart (a right-half part in FIG. 12E) in the thickness direction (thelateral direction in FIG. 12E).

Conversely, second fitting part 76 f has, in the other half part (theleft-half part of FIG. 12E) in the thickness direction, protrusion 85 cprotruding to one side in the normal direction more than one half partand having a flat surface at the tip.

In the case of the present embodiment, one half part in the thicknessdirection is one of a front-half part and a rear-half part in secondfitting part 76 f. On the other hand, the other half part in thethickness direction is the other of the front-half part and therear-half part in second fitting part 76 f. Note that the dimension ofsecond fitting part 76 f in the thickness direction (the lateraldirection in FIG. 12E) may only be a dimension by which right-side wire83 a or left-side wire 83 b can be fitted.

Wire fitting notch 87 has a rectangular cross-sectional shape when cutalong a virtual plane parallel to the normal direction and the thicknessdirection. Right-side wire 83 a or left-side wire 83 b is fitted intowire fitting notch 87 described above.

APPENDIX

Although not illustrated, as Modification 1 of frame 16 a according toEmbodiment 2, each of the right-side rim and the left-side rim may havea lower rim element (also referred to as first rim element) to hold theouter peripheral lower part of each of lenses 14 a, 12 a in place ofupper rim elements 200. In this case, side rim elements (also referredto as second rim element and third rim element) corresponding to firstside rim element 201 and second side rim element 202 described above maybe provided as appropriate.

As Modification 2 of frame 16 a according to Embodiment 2, aconfiguration with right-side wire 83 a and left-side wire 83 b omittedtherefrom may be employed. In this case, lenses 14 a, 12 a are fixed toright-side wire 83 a and left-side wire 83 b with fastening parts (forexample, screws). For this reason, second fitting part 76 b describedabove can be omitted.

Embodiment 3

Embodiment 3 according to the present invention will be described below.First, how the configuration of the present embodiment has been achievedwill be described. PTL 1 described above discloses the lens of eyewear.In this lens, a focal length of a part of region can be changed based onenergization of an electrode provided in the lens. This enables a userof eyewear provided with such a lens as described above to favorablyview a thing disposed near the user through the above part of the region(that is, in a magnified view). In such a lens, the electrode desirablydoes not disturb the field of view from the viewpoint of improving thevisibility. Accordingly, the present inventors have devised theconfiguration of the present embodiment for the purpose of providing alens, a lens blank, and eyewear that can improve the visibility whilepreventing an electrode from disturbing the field of view.

Hereinafter, electronic glasses 10 b as eyewear according to the presentembodiment will be described with reference to FIGS. 13 to 16 . Notethat a basic configuration of electronic glasses 10 b is similar to thatof electronic glasses 10 of Embodiment 1 which has been described withreference to FIGS. 1 and 2 . Thus, for description of portions similarto those in Embodiment 1, numerals similar to those in FIGS. 1 and 2will be used.

As illustrated in FIGS. 13 and 14 , in electronic glasses 10 b of thepresent embodiment, a focal length (power) can be changed in a part ofeach of left and right lenses 12, 14 by a switching operation of theuser. Specifically, electronic glasses 10 b are provided with frame 16to be worn by the user, a pair of left and right lenses 12, 14 held inframe 16, and liquid crystal driver 20 that drives liquid crystal 18provided in lenses 12, 14.

Frame 16 has right-side rim 22, left-side rim 24, and bridge 26.Right-side rim 22 and left-side rim 24 hold right-side lens 14 andleft-side lens 12, respectively. Right-side rim 22 and left-side rim 24each have an annular shape in a front view (seen from the front side ofa user of electronic glasses 10 b).

Bridge 26 links between right-side rim 22 and left-side rim 24 in thelateral direction. Frame 16 has pad parts 28, to be fitted onto the noseof the user, in portions of right-side rim 22 and left-side rim 24, theportions being adjacent to bridge 26.

Frame 16 is provided with right-side temple 30 attached to a right-sideend part of right-side rim 22 so as to be movable in an inclined manner,and left-side temple 32 attached to a left-side end part of left-siderim 24 so as to be movable in an inclined manner.

As illustrated in FIG. 13 , right-side temple 30 has right-side templebody 34 and lid part 38. Right-side temple body 34 has groove part 36with the user side (also referred to as the inner side in the widthdirection) opened. Lid part 38 is attached to right-side temple body 34to close groove part 36.

Liquid crystal driver 20 changes the arrangement of liquid crystal 18provided in each of lenses 12, 14 described later. Liquid crystal driver20 has control module 40, flexible cable 42, battery 44, and switch 46.Each of flexible cable 42, battery 44, and switch 46 is connected tocontrol module 40.

Control module 40 is disposed in groove part 36 of right-side templebody 34. Control module 40 is not exposed to the user side in a statewhere lid part 38 is attached to right-side temple body 34. Switch 46 isfixed to the opposite side of right-side temple body 34 from the user(the outer side in the width direction, and the side opposite to theside where groove part 36 is formed).

Note that switch 46 of the present embodiment is a capacitive touchswitch that is operable by the user's touch. Battery 44 is removablyattached to a rear end part of right-side temple 30.

Flexible cable 42 is provided from control module 40, disposed inright-side temple 30, extending to an upper-side portion of right-siderim 22, bridge 26, and upper-side portion of left-side rim 24.

Then, right-side lens 14 and left-side lens 12 are fixed to (mountedinto) right-side rim 22 and left-side rim 24, respectively. In thisstate, flexible cable 42 and internal electrodes 48, 50 (see FIG. 15 )are connected electrically.

Inside each of lenses 12, 14, a pair of conductive films (notillustrated) are arranged so as to sandwich liquid crystal 18therebetween in the direction of axis FR. Internal electrodes 48, 50 areelectrically connected to one and the other of the pair of conductivefilms, respectively.

When a voltage is applied to internal electrodes 48, 50, the voltage isapplied across the pair of conductive films. The orientation of liquidcrystal 18 is controlled by an electric field generated due to theapplication of the voltage across the conductive films. For example,when cholesteric liquid crystal is employed as liquid crystal 18, arefractive index of liquid crystal 18 is controlled by controlling thevoltage across internal electrodes 48 and 50.

Next, lenses 12, 14 being main parts of the present embodiment will bedescribed. Note that right-side lens 14 and left-side lens 12 are formedto be symmetrical. Therefore, in the following, left-side lens 12 willbe described, and for each part of right-side lens 14, the same numeralas that of left-side lens 12 will be provided and the description ofright-side lens 14 will be omitted.

As illustrated in FIG. 15 , lens 12 is obtained by processing lens blank52 into a shape corresponding to the shape of left-side rim 24 (see FIG.13 ). The external shape of lens blank 52 in a front view is a circularshape, for example. Note that the center (gravity center) of lens blank52 as seen from the front (thickness direction) is referred to as blankcenter C1.

Lens blank 52 is provided with blank body 58. Blank body 58 has frontlens 54 and diffraction-section including lens 56 that are superimposedand joined in the thickness direction. Each of front lens 54 anddiffraction-section including lens 56 is gently curved so as to form ashape protruding forward.

In addition, front lens 54 and a portion of diffraction-sectionincluding lens 56, the portion being except for a portion provided withdiffraction section 60 (see FIG. 14 ), are joined via an adhesive layer(not illustrated). Note that internal electrodes 48, 50 described laterare buried in this adhesive layer. The configuration of lens body 68 oflens 12, cut out of lens blank 52, corresponds to the configuration ofblank body 58 of lens blank 52.

Diffraction-section including lens 56 has, in a part thereof,diffraction section 60 constituting an electroactive section and a partof a focal-length changing section. Diffraction section 60 has aconfiguration of a so-called Fresnel lens that has a saw-blade shape ina cross section on the front lens 54 side (front side).

Diffraction section 60 is disposed below blank center C1. In diffractionsection 60, outer edge 60A in a front view has an elliptical shape withthe lateral direction taken as a longitudinal direction. Note that thecenter (gravity center) of diffraction section 60 is referred to asdiffraction-section center C2.

A line passing through diffraction-section center C2 and extending inthe vertical direction is diffraction-section center line LC2.Diffraction-section center line LC2 is also the center line ofelectroactive section and the center line of focal-length changingsection. In the present embodiment, diffraction-section center line LC2passes through blank center

Here, as illustrated in FIG. 14 , the position and the range ofdiffraction section 60 are set considering fitting point FP of the userof electronic glasses 10 b. As illustrated in FIGS. 14 and 16 , fittingpoint FP is a point at which pupil P of the user of electronic glasses10 b is located when the user with his or her line of sight matched withthe front in the horizontal direction (vertical 0-degree direction) isseen from the front side.

Generally, the position of pupil P in a long-distance view and theposition of pupil P in a short-distance view are different. In thepresent embodiment, the position of diffraction section 60 with respectto lens body 68 is set so that the user can view an object throughdiffraction section 60 in a short-distance view.

As illustrated in FIGS. 15 and 16 , the position and the range ofdiffraction section 60 are set so that the user of electronic glasses 10b can view the object through diffraction section 60 at the time ofvertically moving the line of sight downward in the range of 10 to 20degrees from the horizontal direction (0-degree direction).

For example, the position of diffraction-section center C2 ofdiffraction section 60 is set at a position 9.5 mm vertically down fromthe fitting point and a position 2 to 2.5 mm horizontally from thefitting point.

Generally, when the user shifts pupil P vertically downward to see ashort-distance sight, the position of pupil P moves inward (in thedirection to the nose side). Accordingly, this can be said that theposition of diffraction-section center C2 of diffraction section 60 ismade inset at the position 2 to 2.5 mm horizontally from the fittingpoint.

Liquid crystal 18 is intervened between diffraction section 60 ofdiffraction-section including lens 56 and front lens 54. Liquid crystal18 has its refractive index changed by application of the voltage(energization). liquid crystal 18 constitutes the electroactive sectionand the other one part of focal-length changing section.

As illustrated in FIG. 15 , a pair of internal electrodes 48, 50 arearranged above diffraction section 60 and blank center C1. The pair ofinternal electrodes 48, 50 linearly extend downward from upper ends 58A,68A of blank body 58 and lens body 68. Further, the pair of internalelectrodes 48, 50 are arranged separately from each other in the lateraldirection (the width directions of blank body 58 and lens body 68) andparallel to each other.

Here, parallel does not need to mean exactly parallel, but the internalelectrodes may only be in an almost parallel state. Internal electrode50 disposed on the left side is disposed on the left side with respectto diffraction-section center line LC2 and on the right side from leftend 60AL of outer edge 60A of diffraction section 60.

Internal electrode 48 disposed on the right side is disposed on theright side with respect to diffraction-section center line LC2 and onthe left side from right end 60AR of outer edge 60A of diffractionsection 60.

In the present embodiment, lower end 50A of internal electrode 50 andlower end 48A of internal electrode 48 are arranged above fitting pointFP and above line VC1 passing through the gravity center (blank centerC1) of blank body 58 and extending in the lateral direction, and lineVC3 passing through gravity center C3 of lens body 68 and extending inthe lateral direction.

Specifically, as illustrated in FIG. 16 , the positions of lower end 50Aof internal electrode 50 and lower end 48A of internal electrode 48 areset so that, when the user of electronic glasses 10 b moves the line ofsight 5 degrees upward from the horizontal direction (0-degreedirection), the line of sight of the user is not disturbed by internalelectrodes 48, 50.

Further, in the present embodiment, the upper end parts of the pair ofinternal electrodes 48, 50 are each disposed in a region formed in asubstantially linear shape at upper end 68A of lens body 68 and extendin a direction orthogonal to the region formed in the linear shape (thatis, the normal direction of the region).

Action and Effect of Present Embodiment

Next, the action and effect of the present embodiment will be described.

The voltage is not applied to liquid crystal 18 in a state where theuser is wearing electronic glasses 10 b illustrated in FIGS. 13 and 14and not operating switch 46. Here, the refractive index of liquidcrystal 18 in the state of no voltage being applied is substantially thesame as those of front lens 54 and diffraction-section including lens56. Hence the power of the portion provided with diffraction section 60in each of left and right lenses 12, 14 is substantially the same as thepower of the portion except for diffraction section 60 in each of leftand right lenses 12, 14.

When the voltage is applied to liquid crystal 18 in accordance with theoperation of switch 46 by the user of electronic glasses 10 b, thearrangement of liquid crystal 18 is changed and the refractive index ofliquid crystal 18 changes. Thereby, the power of the portion providedwith diffraction section 60 in each of left and right lenses 12, 14becomes higher than the power of the portion except for diffractionsection 60 in each of left and right lenses 12, 14. In other words, thefocal length of the portion provided with diffraction section 60 becomesshorter than the focal length of the portion except for diffractionsection 60 in each of left and right lenses 12, 14.

As illustrated in FIG. 15 , in the present embodiment, lower end 50A ofinternal electrode 50 and lower end 48A of internal electrode 48 in lensbody 68 are arranged above fitting point FP. It is thereby possible toprevent internal electrode 50 and internal electrode 48 from disturbingthe field of view at the time when the user views the object throughlenses 12.

Particularly in the present embodiment, the positions of lower end 50Aof internal electrode 50 and lower end 48A of internal electrode 48illustrated in FIG. 15 are set so that, when the user of electronicglasses 10 b moves the line of sight 5 degrees upward with respect tothe horizontal direction (0-degree direction), the line of sight of theuser is not disturbed by internal electrodes 48, 50.

It is thereby possible to prevent internal electrode 50 and internalelectrode 48 from disturbing the field of view in the range of the lineof sight that the user of electronic glasses 10 b uses regularly. Notethat the range of the line of sight that the user of electronic glasses10 b uses regularly is a range at the time when the user of electronicglasses 10 b vertically moves the line of sight downward in the range of5 to 10 degrees from the horizontal direction (0-degree direction).

In the present embodiment, the description has been given of the examplewhere internal electrode 50 disposed on the left side (internalelectrode 50 disposed on the right side in right-side lens 14) isdisposed on the right side from left end 60AL of outer edge 60A ofdiffraction section 60 (disposed on the left side from right end 60AR ofouter edge 60A of diffraction section 60 in right-side lens 14).However, the present invention is not limited thereto.

For example, internal electrode 50 disposed on the left side may bedisposed on the left side from left end 60AL of outer edge 60A ofdiffraction section 60. As thus described, the position of internalelectrode 50 disposed on the left side may be set in a range where allof internal electrode 48 is not scraped off when lens 12 is cut out oflens blank 52.

Alternatively, as illustrated in FIG. 17 , both internal electrode 50disposed on the left side and internal electrode 48 disposed on theright side may be arranged on the left side from left end 60AL of outeredge 60A of diffraction section 60.

To be more specific, in lens 12 of Modification 1 illustrated in FIG. 17, diffraction-section center C2 of diffraction section 60 iseccentrically located rightward from center line LC3 passing throughgravity center C3 of lens body 68 and extending in the verticaldirection.

The pair of internal electrodes 48, 50 are eccentrically locatedleftward from center line LC3. With the above configuration, it ispossible to prevent internal electrode 50 and internal electrode 48 fromdisturbing the field of view in the vertically wide region in the front.

Here, RH is a direction in which the nose is located at the time whenthe user wears the lenses as glasses, and LH is a direction on theopposite side to the nose. In the case of structure illustrated in FIG.17 , in lens 12, internal electrodes 48, 50 are arranged in thedirection on the opposite side to the nose. Hence internal electrodes48, 50 are more unlikely to disturb the field of view than in the caseof being arranged on the nose side.

Further, as Modification 2 illustrated in FIG. 18 , distance WL fromdiffraction-section center line LC2 to internal electrode 50 disposed onthe left side and distance WR from diffraction-section center line LC2to internal electrode 48 disposed on the right side may be set to be thesame.

Distance WL and distance WR do not need to be strictly the samedistance, but may only be distances to almost the same degree. It canalso be said that internal electrodes 48, 50 are arranged to besymmetrical with respect to diffraction-section center line LC2. Here,being symmetrical may only mean that internal electrodes 48, 50 aresubstantially parallel to each other and have lengths to substantiallythe same degree and that distance WL and distance WR are distances tosubstantially the same degree.

Left and right lenses 12, 14 (see FIG. 14 ) are formed using lens blank52 set as thus described, so that lens blank 52 can be shared for bothright and left uses. That is, lens blank 52 for left-side lens 12 andlens blank 52 for right-side lens 14 do not need to be producedseparately.

In the present embodiment, as illustrated in FIGS. 15 and 17 , twoelectrodes, internal electrodes 48, 50, are arranged so as to extenddownward from the substantially horizontal region at upper end 68A oflens body 68.

In other words, in a planar view from the front, the pair ofsubstantially linear internal electrodes 48, 50 substantially parallelto each other are arranged so as to form an angle substantially verticalto the substantially linear region at upper end 68A of lens body 68.

Here, when upper end 68A of lens body 68 has the surface, the pair ofinternal electrodes 48, 50 each having the substantially linear shapeand arranged substantially parallel to each other are arranged so as toform an angle substantially vertical to the region having the samesubstantially planar shape at upper end 68A.

As described above, internal electrodes 48, 50 are arranged on thesubstantially horizontal region on the upper surface of lens body 68,whereby the contact pressure between flexible cable 42 and each ofinternal electrodes 48, 50 increases and stable electric connection canbe realized.

Further, internal electrodes 48, 50 are substantially parallel to eachother and each have the substantially linear shape, and these internalelectrodes are arranged so as to form an angle substantially vertical tothe substantially horizontal region on the upper surface of lens body68, thereby making it possible to allow a little error at the time ofcutting lens body 68 out of lens blank 52.

The present embodiment as thus described is not limited to theconfiguration described above, but is applicable to a configurationother than the configuration described above by being subjected tovarious modification within a range not deviating from the gist of theinvention. Further, the present embodiment can be performed in acombination with other embodiments in a technically consistent range.

Summary of Present Embodiment

The lens, the lens blank, and the eyewear according Embodiment 3described above include the following aspects:

[First Aspect]

A first aspect of the lens according to Embodiment 3 above is providedwith: a lens body; an electroactive section provided in a part of aregion of the lens body; and a pair of electrodes that are used forelectrically controlling the electroactive section while being buried inthe lens body, and are arranged substantially parallel to and separatelyfrom each other in a width direction being a direction orthogonal to avertical direction of the lens body while extending downward from theupper-side end of the lens body, the pair of electrode having lower endparts arranged separately from the electroactive section in the verticaldirection of the lens body.

According to the first aspect, it is possible to prevent the end part ofthe pair of electrodes on the electroactive section side from disturbingthe field of view in the lens body.

[Second Aspect]

A lens according to a second aspect is the lens according to the firstaspect, in which the pair of electrodes are arranged in a region withina range in the width direction where the electroactive section isarranged, the region being separated vertically upward from theelectroactive section.

According to the lens of the second aspect, it is possible to ensure thefield of view between the electroactive section and the lower end partsof the pair of electrodes

[Third Aspect]

A lens according to a third aspect is the lens according to the firstaspect, in which the lower end parts of the pair of electrodes arelocated above a point at which a pupil of a user of the lens is assumedto be located when the user sees the front side.

According to the lens of the third aspect, when the user of the lensviews the front side, it is possible to prevent the pair of electrodesfrom disturbing the field of view

[Fourth Aspect]

A lens according to a fourth aspect is the lens according to the firstaspect, in which the pair of electrodes are arranged substantiallysymmetrically with respect to a center line of the electroactive sectionpassing through a gravity center of the electroactive section as seenfrom a thickness direction of the lens body and extending in thevertical direction of the lens body.

According to the lens of the fourth aspect, the right and left lensescan be formed out of the same one lens blank.

[Fifth Aspect]

A lens according to a fifth aspect is the lens according to the firstaspect, in which the pair of electrodes are arranged in substantiallylinear regions at the upper-side end of the lens body.

According to the lens of the fifth aspect, the upper ends of the pair ofelectrodes can be easily connected to an external electrode.

[Sixth Aspect]

A lens according to a sixth aspect is the lens according to the fifthaspect, in which the pair of electrodes each have the same substantiallylinear shape and are arranged substantially vertically downward from thesubstantially linear region of the lens body.

According to the lens of the sixth aspect, it is possible to bring theupper end parts of the pair of electrodes into contact with the externalelectrode in a stable state.

[Seventh Aspect]

A lens according to a seventh aspect is the lens according to the firstaspect, in which the pair of electrodes each have the substantiallylinear shape and are set to have lengths to the same degree.

According to the lens of the seventh aspect, electric resistance of thepair of electrodes can be set to be almost the same.

[Eighth Aspect]

A lens according to an eighth aspect is the lens according to the firstaspect, in which the pair of electrodes are located above a center lineof the lens body passing through a gravity center of the lens body asseen from a thickness direction of the lens body and extending in thewidth direction.

According to the lens of the eighth aspect, when the user of the lensviews the front side, it is possible to prevent the pair of electrodesfrom disturbing the field of view.

[Ninth Aspect]

A lens according to a ninth aspect is the lens according to the firstaspect, in which the pair of electrodes are arranged on the outside ofone end part of the electroactive section in the width direction of thelens body.

According to the lens of the ninth aspect, it is possible to prevent thepair of electrodes from disturbing the field of view.

[Tenth Aspect]

A lens according to a tenth aspect is the lens according to the firstaspect, in which the gravity center of the electroactive section iseccentrically located in one direction of the width direction from acenter line concerning the width direction of the lens body as seen fromthe thickness direction of the lens body, and the pair of electrodes areeccentrically located in the other direction of the width direction fromthe center line.

According to the lens of the tenth aspect, it is possible to prevent thepair of electrodes from disturbing the field of view.

[Eleventh Aspect]

A lens according to an eleventh aspect is the lens according to thetenth aspect, in which the other direction of the width direction is theopposite direction to the direction in which the nose of the user islocated when the lens body is used.

According to the lens of the eleventh aspect, it is possible to preventthe pair of electrodes from disturbing the field of view.

[Twelfth Aspect]

A lens according to a twelfth aspect is the lens according to the firstaspect, in which one electrode is disposed on one side of the lens bodyin the width direction with respect to the center line of theelectroactive section passing through the gravity center of theelectroactive section and extending in the vertical direction of thelens body as seen from the thickness direction of the lens body, and theother electrode is disposed on the other side of the lens body in thewidth direction with respect to the center line of the electroactivesection and disposed closer to one side of the lens body in the widthdirection than the end of the electroactive section on the other side inthe width direction.

According to the lens of the twelfth aspect, it is possible to ensurethe field of view of the portion between the parts of the pair ofelectrodes in the lens body. In addition, at the time of molding thelens out of the lens blank, both the pair of electrodes can be easilyarranged in the lens body.

[Thirteenth Aspect]

A lens according to a thirteenth aspect is the lens according to thefirst aspect, in which one electrode is disposed on one side of the lensbody in the width direction with respect to the center line of theelectroactive section passing through the gravity center of theelectroactive section and extending in the vertical direction of thelens body as seen from the thickness direction of the lens body, theother electrode is disposed on the other side of the lens body in thewidth direction with respect to the center line of the electroactivesection, and a distance in the width direction of the lens body betweenthe one electrode and the center line of the electroactive section issubstantially the same as a distance in the width direction of the lensbody between the other electrode and the center line of theelectroactive section.

According to the lens of the thirteenth aspect, the lens blank can beused as the lens black for forming the right-side lens and the lensblack for forming the right-side lens at the time of molding the lensout of the lens blank.

[Fourteenth Aspect]

A lens according to a fourteenth aspect is the lens according to any oneof the first to thirteenth aspects, in which the electroactive sectionis a focal-length changing section where a focal length is changed byenergization.

According to the lens of the fourteenth aspect, the focal length of thefocal-length changing section can be changed by energization of thefocal-length changing section via the pair of electrodes.

[Fifteenth Aspect]

A lens blank according to a fifteenth aspect is provided with: a lenssubstrate; an electroactive section provided in a part of a region ofthe lens substrate; and a pair of electrodes that are used forelectrically controlling the electroactive section while being buried inthe lens substrate, and are arranged substantially parallel to andseparately from each other in a width direction being a directionorthogonal to a vertical direction of the lens substrate while extendingdownward from the upper-side end of the lens substrate, the pair ofelectrode having lower end parts arranged separately from theelectroactive section in the vertical direction of the lens substrate.

According to the lens blank of the fifteenth aspect, in the lens formedout of the lens blank, it is possible to prevent the pair of electrodesfrom disturbing the field of view.

[Sixteenth Aspect]

A lens blank according to a sixteenth aspect is the lens blank accordingto the fifteenth aspect, in which the pair of electrodes each have asubstantially linear shape and are arranged substantially symmetricallywith respect to a center line of the lens substrate passing through agravity center of the lens substrate as seen from a thickness directionof the lens substrate and extending in the vertical direction of thelens substrate.

According to the lens blank of the sixteenth aspect, the right-side lensand the left-side lens can be formed out of the lens blank.

[Seventeenth Aspect]

A lens blank according to a seventeenth aspect is the lens blankaccording to the fifteenth or sixteenth aspect, in which the pair ofelectrodes have lengths to the same degree.

According to the lens blank of the seventeenth aspect, the right-sidelens and the left-side lens can be formed out of the lens blank.

[Eighteenth Aspect]

Eyewear according to an eighteenth aspect is provided with: the lensaccording to any one of the first to fourteenth aspects; and a frameincluding a lens holder by which the lens is held, the frame being aportion to be worn by a user.

According to the eyewear of the eighteenth aspect, it is possible toprevent the end part of the pair of electrodes on the electroactivesection side from disturbing the field of view in the lens body of thelens.

Embodiment 4

Embodiment 4 according to the present invention will be described below.First, how the configuration of the present embodiment has been achievedwill be described. On the lens for eyewear disclosed in PTL 2 and a lensblank having the lens, a mark including predetermined information isformed. One surface of the lens disposed in PTL 1 is a convex surfaceand the surface on the opposite side to the one surface is a concavesurface. Such a lens has a permanent mark on the concave surface and alayout mark indicating a reference position on the convex surface.However, when the mark is formed on the surface of the lens, there is apossibility that the mark may disappear or be tampered with. Therefore,the present inventors have devised the configuration of the presentembodiment for the purpose of providing a lens for eyewear, a lens blankhaving the lens, and an eyewear on which a mark hardly disappears or ishardly tampered with.

Hereinafter, electronic glasses 100 as eyewear according to the presentembodiment will be described with reference to FIGS. 19 to 23 . In thefollowing, electronic glasses will be described as a representativeexample of the eyewear according to the present embodiment, theelectronic glasses having lenses that include electroactive regionscapable of changing optical characteristics of the lenses by electriccontrol.

Note that examples of the eyewear include glasses (including electronicglasses or sunglasses) having an auxiliary mechanism for improving theeyesight of the user such as vision corrective lenses, goggles, andvarious devices (for example, glasses-type wearable terminal,head-mounted display, and the like) having a mechanism to presentinformation to the field of view, or the eyes, of the user.

In the present embodiment, electronic binocular glasses having a pair oflenses will be described, but the eyewear is not limited to this aspect.The configuration of the eyewear may be a configuration to be able tohold the following mechanisms by the user wearing the eyewear: anauxiliary mechanism to improve the eyesight, or the field of view, ofthe user, a mechanism to present information to the eyes of the user,and the like.

The eyewear is not limited to a glasses-type to be worn on both ears,but the eyewear may be worn on the head or one ear. Further, the eyewearis not limited to the binocular eyewear, but may be monocular eyewear.

[Configuration of Electronic Glasses]

FIG. 19 is a perspective view illustrating an example of a configurationof electronic glasses 100 according to the present embodiment. Note thata basic structure of electronic glasses 100 according to the presentembodiment is almost similar to that of electronic glasses 10 accordingto Embodiment 1 which has been described with reference to FIGS. 1 and 2. FIG. 20 is a block diagram illustrating an internal circuit ofelectronic glasses 100 according to the present embodiment. Electronicglasses 100 has a pair of lenses 110, frame 120, and power source 160.

Frame 120 has front 130 and a pair of temples 140. In the following, aportion where front 130 is disposed will be described as the front ofelectronic glasses 100 and lenses 110. Note that temple 140 for theright side and front 130 are exploded in FIG. 19 .

The pair of lenses 110 are formed so as to be almost symmetrical in afront view (also referred to as a planar view from the front-reardirection or the thickness direction) of electronic glasses 100, andhave the same constituent elements. Therefore, in the following, lens110 for right eye in electronic glasses 100 will be described, and thedescription of the constituents of the configuration of lens 110 forleft eye will be omitted.

As illustrated in FIG. 19 , front 130 holds a pair of lenses 110. Front130 has a pair of rims 131 respectively supporting the pair of lenses110, and bridge 132 connecting between the pair of rims 131.

The shape of rim 131 is a shape corresponding to the shape of lens 110.Bridge 132 has a pair of nose pads 133 that can come into contact withthe nose of the user. As illustrated in FIG. 19 , wiring 180 is disposedinside front 130.

Wiring 180 electrically connects between control section 150 and oneelectrode (first transparent conductive layer 114 and first auxiliaryelectrode 117 described later) of lens 110, and electrically connectsbetween control section 150 and the other electrode (second transparentconductive layer 116 and second auxiliary electrode 119 described later)of lens 110. In the case of the present embodiment, first auxiliaryelectrode 117 corresponds to internal electrodes 48, 50 (see FIG. 4 ) inEmbodiment 1 described above.

A material for front 130 is not particularly limited. As the materialfor front 130, a known material to be used as a material for the frontof glasses can be used. Examples of the material for front 130 includepolyamide, acetate, carbon, celluloid, polyetherimide, and polyurethane.

The pair of temples 140 are formed so as to be almost symmetrical inelectronic glasses 100 and have mutually the same constituent elements.Therefore, in the following, temple 140 for the right side will bedescribed, and for constituents of temple 140 for the left side, thesame numerals as those of constituents of temple 140 for the right sidewill be provided and the description of temple 140 for the left sidewill be omitted.

Temple 140 is connected to front 130 in the front end part thereof. Forexample, temple 140 is rotatably fitted into rim 131 of front 130.

As illustrated in FIG. 19 , temple 140 has housing 141, detectionsection 142, and control section 150.

Housing 141 constitutes an external shape of temple 140. Housing 141stores detection section 142, control section 150, and a part of wiring180. Housing 141 extends along one direction. The shape of housing 141is not particularly limited.

From the viewpoint of facilitating the user to recognize the position ofdetection section 142, the shape of a part of housing 141 and the shapeof the other portion of housing 141 may be different from each other. Inthe present embodiment, the shape of a part of housing 141 and the shapeof the other portion of housing 141 are different from each other.

A protruding strip is formed on the left-side surface of housing 141(the outer-side surface of electronic glasses 100). The position of theleft-side surface of housing 141 which corresponds to detection section142 is formed to have a planar shape. This enables the user to easilyrecognize the position where detection section 142 is disposed. Inaddition, the shape of the right-side surface of housing 141 (theinner-side surface of electronic glasses 100) is a planar shape.

A material for housing 141 is not particularly limited. As the materialfor housing 141, a known material to be used as a material for a templeof glasses can be used. Examples of the material for housing 141 are thesame as the examples of material for front 130. From the viewpoint offacilitating the user to recognize the position of detection section142, a material for a part of housing 141 and a material for the otherportions of housing 141 may be different from each other

Detection section 142 has a capacitive detection pad, for example. Asthe detection pad, a known detection pad usable as a touch sensor can beused. When an object (the finger of the user, or the like) touches aposition of housing 141 which corresponds to detection section 142,detection section 142 detects a change in capacitance generated by thetouch.

Control section 150 is electrically connected to the detection pad ofdetection section 142 and the electrodes (first transparent conductivelayer 114, first auxiliary electrode 117, second transparent conductivelayer 116, and second auxiliary electrode 119) of lens 110 via wiring180.

Control section 150 controls a voltage across first transparentconductive layer 114 and second transparent conductive layer 116 tocontrol an optical characteristic of first region 1101 (described later)of lens 110. More specifically, when detection section 142 detects atouch of the object, control section 150 applies the voltage to apredetermined region of each of the pair of lenses 110 or stops applyingthe voltage and switches the optical characteristic (a focal length inthe present embodiment) of first region 1101 (see FIG. 20 ).

Control section 150 has a control circuit that, for example, drives thedetection pad and detects a change in capacitance in the detection pad.Control section 150 also has a control circuit that controls applicationof the voltage across first transparent conductive layer 114 and secondtransparent conductive layer 116 (liquid crystal layer 115 in thepresent embodiment) of lens 110.

Control section 150 is, for example, mounted in detection section 142 ina state connected to the detection pad so as to receive results ofdetection of the change in capacitance in the detection pad.

Power source 160 supplies electric power to detection section 142 andcontrol section 150 (see FIG. 20 ). In the present embodiment, powersource 160 is a rechargeable battery pack removably held in the otherend part (rear end part) of temple 140. Examples of power source 160include a nickel-metal hydride battery.

(Configuration of Lens)

FIG. 21 schematically illustrates an example of the configuration oflens 110 and is an exploded sectional view schematically illustratingthe configuration of lens 110 cut along a line C-C of FIG. 19 .

As illustrated in FIG. 21 , lens 110 has first transparent substrate111, second transparent substrate 112 disposed on first transparentsubstrate 111, and intermediate layer 113. Intermediate layer 113 isdisposed between first transparent substrate 111 and second transparentsubstrate 112. Although detailed in later, mark M including informationis formed in intermediate layer 113.

Lens 110 has first region (electroactive region) 1101 where a focallength (power) is switchable with the voltage, and second region 1102placed in a region except for first region 1101. Lens 110 may be aspherical lens or an aspherical lens. The shape of lens 110 can beappropriately adjusted in accordance with expected optical power.

The shape, size, and position of first region 1101 can be appropriatelydesigned in accordance with the size of lens 110, the use of lens 110,and the like. Examples of the use of lens 110 include a near-and-farbifocal lens, a near-and-mid bifocal length, and near-and-near bifocallens. As illustrated in FIG. 19 , first region 1101 is placed below thecenter part of lens 110 in a front view of lens 110.

First region 1101 has first transparent substrate 111, first transparentconductive layer 114, liquid crystal layer 115, second transparentconductive layer 116, and second transparent substrate 112. Intermediatelayer 113 in first region 1101 has first transparent conductive layer114, liquid crystal layer 115, and second transparent conductive layer116.

Second region 1102 has first transparent substrate 111, first auxiliaryelectrode 117, first transparent conductive layer 114, adhesive layer118, second transparent conductive layer 116, second auxiliary electrode119, and second transparent substrate 112.

Intermediate layer 113 in second region 1102 has first auxiliaryelectrode 117, first transparent conductive layer 114, adhesive layer118, second transparent conductive layer 116, and second auxiliaryelectrode 119. In the present embodiment, mark M is formed in secondtransparent conductive layer 116 on second region 1102.

Each constituent of lens 110 has translucency to visible light.

First transparent substrate 111 is disposed on the rear side (the userside) of lens 110 in electronic glasses 100. First transparent substrate111 is curved toward the front side of electronic glasses 100 so as tohave a protruding shape. The curvature and the shape of firsttransparent substrate 111 can be appropriately adjusted in accordancewith the expected optical power.

The size of first region 1101 and the shape thereof in a planar view canbe appropriately adjusted in accordance with the breadth of the visualfield of a human. For example, first region 1101 is preferably formed soas to have a lateral length larger than a vertical length.

In the present embodiment, the shape of first region 1101 in a planarview is an elliptical shape. In the present specification, the shape offirst region 1101 in the planar view means the shape of first region1101 as seen from a point located on an optical axis of light incidenton lens 110 on the front side of electronic glasses 100.

On one surface of first transparent substrate 111, first region 1101 isformed with spherical protrusion 1103 disposed at the center portion anda plurality of annular protruding strips 1104 arranged on the outside ofprotrusion 1103.

The plurality of protruding strips 1104 are arranged concentrically. Inthe present specification, the “outside” means a position more distantfrom the center of the first region (also the center of protrusion 1103)along the direction orthogonal to the optical axis of the light incidenton lens 110 from the front side of electronic glasses 100 in a statewhere lens 110 is in use (a state where lens 110 is incorporated inelectronic glasses 100 and in use).

The shapes of protrusion 1103 and protruding strip 1104 can beappropriately adjusted in accordance with the expected optical power atthe time of diffracting light having been incident from the front ofelectronic glasses 100. Examples of the shapes of protrusion 1103 andprotruding strip 1104 include a Fresnel-lens shape. A part of each ofprotrusion 1103 and protruding strip 1104 may have the Fresnel-lensshape, or all of each of protrusion 1103 and protruding strip 1104 mayhave the Fresnel-lens shape.

A material for first transparent substrate 111 is not particularlylimited so long as having translucency. For example, as the material forfirst transparent substrate 111, a known material usable as a materialfor a lens can be used.

Examples of the material for first transparent substrate 111 includeglass and resin. Examples of the resin include polymethyl methacrylate,polycarbonate, polydiethyleneglycol bis allyl carbonate, andpolystyrene.

First transparent conductive layer 114 and second transparent conductivelayer 116 are a pair of transparent conductive layers havingtranslucency. First transparent conductive layer 114 and secondtransparent conductive layer 116 in first region 1101 are a pair oftransparent electrodes for application of the voltage across firsttransparent conductive layer 114 and second transparent conductive layer116 (liquid crystal layer 115 in the present embodiment).

First transparent conductive layer 114 is disposed on first transparentsubstrate 111 side in intermediate layer 113. In the present embodiment,first transparent conductive layer 114 is disposed on the surface offirst transparent substrate 111 on the second transparent substrate 112side.

Second transparent conductive layer 116 is disposed on secondtransparent substrate 112 side in intermediate layer 113. In the presentembodiment, second transparent conductive layer 116 is disposed on thesurface of second transparent substrate 112 on the first transparentsubstrate 111 side.

First transparent conductive layer 114 and second transparent conductivelayer 116 may only be disposed at least over a range (first region 1101)where the voltage can be applied to liquid crystal layer 115. Hencefirst transparent conductive layer 114 and second transparent conductivelayer 116 may be disposed in second region 1102 or may not be disposed.

From the viewpoints of making first transparent conductive layer 114 andsecond transparent conductive layer 116 externally inconspicuous andholding down manufacturing cost of lens 110, first transparentconductive layer 114 and second transparent conductive layer 116 arepreferably arranged substantially all over first region 1101 and secondregion 1102.

In the present embodiment, first transparent conductive layer 114 andsecond transparent conductive layer 116 are arranged substantially allover first region 1101 and second region 1102.

FIGS. 22A and 22B are assembly diagrams each illustrating an example ofthe configuration of a part of the lens. FIG. 22A is an assembly diagramof first transparent substrate 111, first transparent conductive layer114, and first auxiliary electrode 117 in the case of viewing lens 110from second transparent substrate 112 side. Meanwhile, FIG. 22B is anassembly diagram of second transparent substrate 112, second transparentconductive layer 116, and second auxiliary electrode 119 in the case ofviewing lens 110 from first transparent substrate 111 side.

From the viewpoint of lowering the possibility of an electric shortcircuit in first transparent conductive layer 114 and second transparentconductive layer 116 in intermediate layer 113, it is preferable to use,as the electrode, only a portion of each of first transparent conductivelayer 114 and second transparent conductive layer 116, the portion beingnecessary for application of the voltage to liquid crystal layer 115.

From the viewpoint as thus described, in the present embodiment, firsttransparent conductive layer 114 has first slit 1141 and second slit1142 for insulation (see dotted lines of FIG. 22A).

More specifically, first slit 1141 is formed in first transparentconductive layer 114 so that a region including first region 1101 and aportion of second region 1102 where first auxiliary electrode 117 isdisposed and a region except for the above region are insulated fromeach other.

Further, second slit 1142 is formed in first transparent conductivelayer 114 so that a region including a portion of second region 1102which corresponds to second auxiliary electrode 119 and a region exceptfor the above region are insulated from each other.

In the present embodiment, second transparent conductive layer 116 hasthird slit 1161 and fourth slit 1162 for insulation (see dotted lines ofFIG. 22B).

More specifically, third slit 1161 is formed in second transparentconductive layer 116 so that a region including first region 1101 and aportion of second region 1102 where second auxiliary electrode 119 isdisposed and a region except for the above region are insulated fromeach other.

Further, fourth slit 1162 is formed in second transparent conductivelayer 116 so that a region including a portion of second region 1102which corresponds to first auxiliary electrode 117 and a region exceptfor the above region are insulated from each other.

Each of first transparent conductive layer 114 and second transparentconductive layer 116 has a thickness not particularly limited so long asbeing able to function as the transparent electrode. For example, thethickness of each of first transparent conductive layer 114 and secondtransparent conductive layer 116 is from 5 to 50 nm.

The thickness of each of first transparent conductive layer 114 andsecond transparent conductive layer 116 can be appropriately adjusted inaccordance with a material for each of these layers. Although detailedin later, in the present embodiment, mark M is formed by printing orengraving on second transparent conductive layer 116.

Here, the engraving means cutting off or machining a part of secondtransparent conductive layer 116 to form any of a letter, a figure, asymbol, a barcode, and a trademark, or a combination of these.

The material for each of first transparent conductive layer 114 andsecond transparent conductive layer 116 is not particularly limited solong as having expected translucency and conductivity. Examples of thematerial for each of first transparent conductive layer 114 and secondtransparent conductive layer 116 include Indium tin oxide (ITO) and zincoxide (ZnO). The material for first transparent conductive layer 114 andthe material for second transparent conductive layer 116 may be the sameas or different from each other.

Liquid crystal layer 115 is disposed between first transparent substrate111 and second transparent substrate 112. Liquid crystal layer 115 maybe sandwiched directly between first transparent substrate 111 andsecond transparent substrate 112, or another constituent may be disposedbetween first transparent substrate 111 and liquid crystal layer 115 orbetween liquid crystal layer 115 and second transparent substrate 112.

In the present embodiment, liquid crystal layer 115 is disposed betweenfirst transparent conductive layer 114 and second transparent conductivelayer 116 in a region corresponding to first region 1101. The shape ofliquid crystal layer 115 is a shape corresponding to the shapes ofprotrusion 1103 and the plurality of annular protruding strips 1104 infirst region 1101.

Liquid crystal layer 115 is configured so as to change its refractiveindex in accordance with application or non-application of the voltage.Although detailed in later, for example, in a state where no voltage isbeing applied to liquid crystal layer 115, the refractive index ofliquid crystal layer 115 is almost the same as the refractive index offirst transparent substrate 111 and the refractive index of secondtransparent substrate 112.

On the other hand, in a state where the voltage is being applied toliquid crystal layer 115, the refractive index of liquid crystal layer115 can be adjusted so as to be different from the refractive index offirst transparent substrate 111 and the refractive index of secondtransparent substrate 112.

Liquid crystal layer 115 contains a liquid crystal material. An orientedstate of the liquid crystal material at the time when the voltage isbeing applied and an oriented state of the liquid crystal material atthe time when no voltage is being applied are different from each other.The liquid crystal material can be appropriately adjusted in accordancewith the refractive index of first transparent substrate 111 and therefractive index of second transparent substrate 112. Examples of theliquid crystal material include cholesteric liquid crystal and nematicliquid crystal.

Second transparent substrate 112 is disposed on first transparentsubstrate 111 so as to sandwich first transparent conductive layer 114,liquid crystal layer 115, and second transparent conductive layer 116.Second transparent substrate 112 is disposed on the front side of lens110 in electronic glasses 100.

Second transparent substrate 112 is also curved toward the front side ofelectronic glasses 100 so as to have a protruding shape. The curvatureof second transparent substrate 112 corresponds to the curvature offirst transparent substrate 111. Examples of the material for secondtransparent substrate 112 are the same as the examples of the materialfor first transparent substrate 111.

In second region 1102, adhesive layer 118 is disposed between firsttransparent substrate 111 and second transparent substrate 112 to makefirst transparent substrate 111 and second transparent substrate 112adhere to each other.

When first transparent conductive layer 114 and second transparentconductive layer 116 are also disposed in second region 1102, adhesivelayer 118 is disposed between first transparent conductive layer 114 andsecond transparent conductive layer 116. Adhesive layer 118 also has afunction to seal the liquid crystal material constituting liquid crystallayer 115.

Adhesive layer 118 is made of a hardened material of an adhesive. Thematerial for the adhesive is not particularly limited so long as havingexpected translucency and being able to adequately make firsttransparent substrate 111 and second transparent substrate 112 adhere toeach other. An adhesive having an expected refractive index is selectedfrom the viewpoint of adjusting optical power of lens 110.

In the front view of lens 110, first auxiliary electrode 117 extendsinward from the outer edge of lens 110 and is electrically connected tofirst transparent conductive layer 114 (see FIG. 22A). In the presentembodiment, first auxiliary electrode 117 is disposed between firsttransparent substrate 111 and first transparent conductive layer 114 insecond region 1102.

First auxiliary electrode 117 is a transparent electrode having athickness to some degree. Wiring 180 (see FIG. 19 ) connected to anexternal circuit (control section 150 in the present embodiment) andfirst transparent conductive layer 114 come into contact with each otherat the outer edge of lens 110.

The total of the contact area between wiring 180 and first auxiliaryelectrode 117 and the contact area between wiring 180 and firsttransparent conductive layer 114 is large as compared with the contactarea between the wiring 180 and first transparent conductive layer 114.Hence the external circuit and first transparent conductive layer 114can be more reliably connected electrically.

The position, the thickness, and the shape of first auxiliary electrode117 are not particularly limited so long as the above function can beexerted. From the viewpoint of contact with wiring 180, first auxiliaryelectrode 117 may only be exposed in the outer edge part of lens 110. Inthe present embodiment, first auxiliary electrode 117 extends from theupper edge of lens 110 to the center part of lens 110 in the front viewof lens 110. The shape of first auxiliary electrode 117 in a planar viewis not particularly limited but may, for example, be a linear shape. Thethickness of first auxiliary electrode 117 is, for example, from 0.1 to50 μm.

In the front view of lens 110, second auxiliary electrode 119 extendsinward from the outer edge of lens 110 and is electrically connected tosecond transparent conductive layer 116. In the present embodiment,second auxiliary electrode 119 is disposed between second transparentsubstrate 112 and second transparent conductive layer 116 in secondregion 1102.

Second auxiliary electrode 119 is also a transparent electrode having athickness to some degree from a similar viewpoint to first auxiliaryelectrode 117. The position, the thickness, and the shape of secondauxiliary electrode 119 are similar to the position, thickness, and theshape of first auxiliary electrode 117.

The positional relation between first auxiliary electrode 117 and secondauxiliary electrode 119 is not particularly limited so long as the abovefunction can be exerted. For example, each of first auxiliary electrode117 and second auxiliary electrode 119 may each extend inward from oneouter edge of lens 110, or may extend inward from both outer edges oflens 110 located in positions opposite to each other.

In the present embodiment, in the front view of lens 110, firstauxiliary electrode 117 and second auxiliary electrode 119 are arrangedso as to be adjacent to each other and each extend inward from one outeredge of lens 110. In the present specification, that first auxiliaryelectrode 117 and second auxiliary electrode 119 are “adjacent” to eachother means that a space (the shortest distance) between first auxiliaryelectrode 117 and second auxiliary electrode 119 is from 2 to 48 mm

Intermediate layer 113 may further have another constituent havingtranslucency, as required. Examples of another constituent include aninsulating layer and an oriented film.

The insulating layer prevents an electric short circuit between firsttransparent conductive layer 114 and second transparent conductive layer116 via liquid crystal layer 115. For example, the insulating layer isdisposed between first transparent conductive layer 114 and liquidcrystal layer 115, and the insulating layer is also disposed betweenliquid crystal layer 115 and second transparent conductive layer 116. Asa material for the insulating layer, a known material usable as aninsulating layer having translucency can be used. Examples of thematerial for the insulating layer include silicon dioxide.

The oriented film controls the oriented state of the liquid crystalmaterial in liquid crystal layer 115. For example, the oriented film isdisposed between first transparent conductive layer 114 and liquidcrystal layer 115, and between liquid crystal layer 115 and secondtransparent conductive layer 116. As a material for the oriented film, aknown material usable as an oriented film of the liquid crystal materialcan be used. Examples of the material for the oriented film includepolyimide.

Mark M is formed in intermediate layer 113, that is, on at least onelayer constituting intermediate layer 113. Mark M may be a through holeformed in the layer in a predetermined pattern, or may be a fluorescencedye disposed on the layer in a predetermined pattern.

Mark M can be formed by engraving or printing on the layer. In thepresent embodiment, mark M is a through hole formed in a predeterminedpattern in a part of second transparent conductive layer 116. Mark M ismade of the through hole formed in a transparent layer in intermediatelayer 113, and is thus inconspicuous as compared with a mark formed ofcolored ink, for example.

Although detailed in later, from the viewpoint of preventing an increasein time for manufacturing lens 110, mark M is preferably formed in oneor both of first transparent conductive layer 114 and second transparentconductive layer 116.

Mark M has various pieces of information on lens 110. Examples of mark Minclude a letter, a figure, a symbol, a barcode, and a trademark.Examples of the information include information on manufacturing of lens110, information on the material for lens 110, information onperformance of lens 110, information on structural features of lens 110,information used at the time of sale of lens 110, and information ontransportation of lens 110.

Mark M includes at least one piece of the information described above.Examples of the information on manufacturing of lens 110 include amanufacturing number, a date manufactured, manufacturing certificationby a manufacturer, and a model name provided by a manufacturing company.

Examples of the information on the material for lens 110 includeinformation on traceability of the material, raw materials, and the likeof lens 110. Examples of the information on the characteristics of lens110 include information on optical characteristics such as a power and arefractive index of lens 110. Examples of the characteristics of lens110 include a distance between the electrodes, a power for long sight,and a power for short sight.

The position of mark M is not particularly limited but is preferably aposition hardly visible from the user using electronic glasses 100. Fromthe viewpoint of the visibility of the user, mark M is preferably placedbelow a horizontal line passing through the center of gravity of lens110 in the front view of lens 110.

Further, mark M is preferably placed on the laterally outer side ofelectronic glasses 100 than a vertical line passing through the centerof gravity of lens 110 in the front view of lens 110. In the presentembodiment, mark M is placed so as to be adjacent to first region 1101in the laterally outer-side region of electronic glasses 100 in thefront view of electronic glasses 100.

As thus described, from the viewpoint of mark M being hardly visiblefrom the user using electronic glasses 100, it is preferable that mark Mbe placed below the horizontal line passing through the center ofgravity of lens 110 and on the laterally outer side of electronicglasses 100 from the vertical line passing through the center of gravityof lens 110 in the front view of lens 110.

Further, from the above viewpoint, mark M is preferably placed on themore opposite side to the user of electronic glasses 100 (lens 110) thanthe middle point of intermediate layer 113 (placed on the front side ofelectronic glasses 100) in the thickness direction of lens 110.

That is, in intermediate layer 113, mark M is preferably placed on thelayer located closer to second transparent substrate 112 than liquidcrystal layer 115. For example, mark M is preferably formed in secondtransparent conductive layer 116. In the present embodiment, mark M isformed in second transparent conductive layer 116.

[Configuration of Lens Blank]

Lens 110 may be configured together with blank part 170 as a unit. FIG.23 illustrates an example of a configuration of lens blank 2000. FIG. 23is a front view of lens blank 2000. In FIG. 23 symbol d_(M) denotes aspace (the shortest distance) between mark M and first region 1101.

As illustrated in FIG. 23 , lens blank 2000 has lens 110 and blank part170. Lens 110 and blank part 170 are formed as a unit. The externalshape of lens blank 2000 in a planar view from the front-rear direction(the state illustrated in FIG. 23 ) is not particularly limited but is,for example, a circular shape.

Blank part 170 is disposed on the outer side of lens blank 2000 so as tosurround lens 110. The configuration of blank part 170 is the same asthe configuration of second region 1102 in lens 110, for example.

In the planar view of lens blank 2000, each of first auxiliary electrode117 and second auxiliary electrode 119 extends inward from the outeredge of lens blank 2000. That is, in the planar view of lens blank 2000,each of first auxiliary electrode 117 and second auxiliary electrode 119crosses the inner edge of blank part 170 from the outer edge of blankpart 170 and extends to the inside of lens 110.

Although not particularly illustrated, in blank part 170, each of firstslit 1141, second slit 1142, third slit 1161, and fourth slit 1162 alsoextends inward from the outer edge of lens blank 2000 in accordance withthe range in which each of first auxiliary electrode 117 and secondauxiliary electrode 119 extends.

[Lens Manufacturing Method]

Lens 110 can be manufactured by, for example, the followingmanufacturing method. First, lens blank 2000 is manufactured.Specifically, first transparent substrate 111 and second transparentsubstrate 112 are prepared. First transparent substrate 111 and secondtransparent substrate 112 can be manufactured by injection molding, forexample.

Subsequently, first auxiliary electrode 117 is formed in a predeterminedposition on first transparent substrate 111, and second auxiliaryelectrode 119 is formed in a predetermined position on secondtransparent substrate 112. Examples of a method for forming firstauxiliary electrode 117 on first transparent substrate 111 and a methodfor forming second auxiliary electrode 119 on second transparentsubstrate 112 include vacuum evaporation and sputtering.

Next, first transparent conductive layer 114 is formed on firsttransparent substrate 111 on which first auxiliary electrode 117 isformed, and second transparent conductive layer 116 is formed on secondtransparent substrate 112 on which second auxiliary electrode 119 isformed. Examples of a method for forming first transparent conductivelayer 114 on first transparent substrate 111 and a method for formingsecond transparent conductive layer 116 on second transparent substrate112 include vacuum evaporation and sputtering.

First transparent conductive layer 114 may be formed on the wholesurface of first transparent substrate 111 or may be formed on a part ofthe surface. However, for forming first transparent conductive layer 114only on a part of the surface of first transparent substrate 111, otherparts such as a mask may need to be prepared or installed.

Thus, from the viewpoint of preventing an increase in manufacturing costand manufacturing time for lens 110 (lens blank 2000), first transparentconductive layer 114 is preferably formed on the whole surface of firsttransparent substrate 111.

As described above, also from the viewpoint of making first transparentconductive layer 114 externally inconspicuous, first transparentconductive layer 114 is preferably formed on the whole surface of firsttransparent substrate 111. The same applies to second transparentconductive layer 116.

Subsequently, mark M is formed in intermediate layer 113. In the presentembodiment, mark M is formed in second transparent conductive layer 116.

A method for forming mark M is not particularly limited so long as beingable to adequately form mark M in intermediate layer 113. Examples ofthe method for forming mark M include laser marking and making-off.

From the viewpoint of the clearness of mark M and manufacturing cost,the method for forming mark M is preferably laser marking. For example,when a conductive material constituting each of first transparentconductive layer 114 and second transparent conductive layer 116contains ITO, mark M can be engraved in an ITO conductive layer by anyttrium-aluminum-garnet (YAG) laser or yttrium-vanadate (YVO4) laserhaving an ITO absorption wavelength.

Note that mark M may also be formed by the following method. Forexample, mark M may be formed by previously placing ink in apredetermined pattern on second transparent substrate 112, formingsecond transparent conductive layer 116, and then removing secondtransparent conductive layer 116 disposed on the ink, along with theink.

When first transparent conductive layer 114 is disposed over the wholesurface of first transparent substrate 111, it is preferable to formfirst slit 1141 and second slit 1142 in first transparent conductivelayer 114. When second transparent conductive layer 116 is disposed overthe whole surface of second transparent substrate 112, it is preferableto form third slit 1161 and fourth slit 1162 in second transparentconductive layer 116.

Examples of a method for forming first slit 1141 and second slit 1142 infirst transparent conductive layer 114 and examples of a method forforming third slit 1161 and fourth slit 1162 in second transparentconductive layer 116 are the same as the examples of the method forforming mark M.

By forming mark M in one or both of first transparent conductive layer114 and second transparent conductive layer 116, it is possible to formmark M at the same time as formation of first slit 1141, second slit1142, third slit 1161, and fourth slit 1162, which is preferred from theviewpoint of preventing an increase in time for manufacturing lens 110(lens blank 2000). Further, from a similar viewpoint, mark M ispreferably formed on one or both of first auxiliary electrode 117 andsecond auxiliary electrode 119.

Subsequently, the liquid crystal material is provided in a portioncorresponding to first region 1101 of first transparent substrate 111where first transparent conductive layer 114 is formed, and the adhesiveis provided in a portion corresponding to second region 1102 of firsttransparent substrate 111. With the liquid crystal material and theadhesive disposed on first transparent substrate 111, second transparentsubstrate 112 formed with second transparent conductive layer 116 isdisposed on first transparent substrate 111. Then, the adhesive ishardened, so that lens blank 2000 can be manufactured.

Finally, lens blank 2000 is processed into expected shape and size, toobtain lens 110 having expected external shape and size. At this time,lens blank 2000 is processed so that each of first auxiliary electrode117 and second auxiliary electrode 119 is included in lens 110. In thepresent embodiment, lens blank 2000 is cut along a dashed-dotted lineillustrated in FIG. 23 , to obtain lens 110.

In the present embodiment as well, similarly to Embodiments 1 to 3described above, on the outer periphery of lens 110, the shape of thefirst region (specifically, first fitting part 74 of Embodiment 1described above) including the portion where first auxiliary electrode117 and second auxiliary electrode 119 are exposed may be madeappropriately different from the shape of the second region(specifically, second fitting part 76 of Embodiment 1 described above)being the portion except for the first region. To such a configuration,the configuration of each of the embodiments described above can beapplied as appropriate.

Lens blank 2000 and lens 110 according to the present embodiment can bemanufactured in such a manner as above. As described above, lens 110 isobtained by processing lens blank 2000 into an expected shape and size.It is thus necessary for mark M to be placed in the region that is cutout as lens 110 in lens blank 2000.

Lens 110 is cut out of lens blank 2000 so as to include first region1101, the tip part of first auxiliary electrode 117, and the tip part ofsecond auxiliary electrode 119. Hence mark M to be placed on lens 110 ispreferably placed near first region 1101 and the tip part of firstauxiliary electrode 117 and near the tip part of second auxiliaryelectrode 119.

For example, in the present embodiment, in the front view of lens 110,at least a part of mark M is preferably placed in a region with distanced_(M) equal to or shorter than 24 mm from first region 1101.

(Modifications)

Meanwhile, the position of mark M is not limited to the positiondescribed above. FIGS. 24A to 24D illustrate examples of configurationsof lens blanks 2000 a to 2000 d according to Modifications 1 to 4 of thepresent embodiment.

FIG. 24A is a front view of lens blank 2000 a according to Modification1 of the present embodiment. FIG. 24B is a front view of lens blank 2000b according to Modification 2 of the present embodiment. FIG. 24C is afront view of lens blank 2000 c according to Modification 3 of thepresent embodiment. FIG. 24D is a front view of lens blank 2000 daccording to Modification 4 of the present embodiment. Lens blanks 2000a to 2000 d are different from lens blank 2000 only in that positions ofmarks Ma to Md are different from the position of mark M.

As described above, the mark to be placed on lens 110 is preferablyplaced in a position to be cut out of lens blank 2000 as lens 110.

As illustrated in FIG. 24A, in the front view of lens 110 a (lens blank2000 a), mark Ma according to Modification 1 is preferably placed nearthe tip part of first auxiliary electrode 117 or the tip part of secondauxiliary electrode 119.

In Modification 1 illustrated in FIG. 24A, mark Ma is placed near thetip part of second auxiliary electrode 119. In Modification 1, in afront view of lens 110 a, at least a part of mark Ma is preferablyplaced in a region with distance d_(Ma) equal to or shorter than 19 mmfrom the one or both of the tip part of first auxiliary electrode 117and the tip part of second auxiliary electrode 119.

As illustrated in FIG. 24B, in a front view of lens 110 b (lens blank2000 b), at least a part of mark Mb according to Modification 2 ispreferably placed between first auxiliary electrode 117 and secondauxiliary electrode 119.

As illustrated in FIG. 24C, in a front view of lens 110 c (lens blank2000 c), at least a part of mark Mc according to Modification 3 ispreferably placed so as to overlap with one or both of first auxiliaryelectrode 117 and second auxiliary electrode 119. In Modification 3,mark Mc is disposed so as to overlap with second auxiliary electrode 119in the front view of lens 110 c.

In Modification 2 (3) described above, at least a part of mark Mb(Mc) ispreferably placed in a region with a distance d_(Mb) (d_(Mc)) equal toor shorter than 12 mm from a virtual line (see a chain double-dashedline of FIGS. 24B (24C)) connecting between the tip part of firstauxiliary electrode 117 and the tip part of second auxiliary electrode119.

As illustrated in FIG. 24D, mark Md according to Modification 4 may beplaced in blank part 170 d. The position of mark Md to be disposed inblank part 170 d is not particularly limited so long as being a regionexcept for the region to be cut out as lens 110 d in lens blank 2000 d.In Modification 4, mark Md is placed between first auxiliary electrode117 and second auxiliary electrode 119 in blank part 170 d.

[Operation of Electronic Glasses]

Subsequently, an example of the operation of electronic glasses 100 willbe described. First, a state (off-state) where no voltage is beingapplied to liquid crystal layer 115 of electronic glasses 100 will bedescribed.

In the off-state, in first region 1101 of lens 110, the refractive indexof liquid crystal layer 115 and the refractive index of each of firsttransparent substrate 111 and second transparent substrate 112 arealmost the same. There thus occurs no lens effect attributable to liquidcrystal layer 115. Therefore, in lens 110, the focal length (power) offirst region 1101 and the focal length (power) of second region 1102 arealmost the same as each other.

When a portion of housing 141 which corresponds to detection section 142is touched by an object being a conductor (for example, the finger ofthe user), the detection pad of detection section 142 detects a changein capacitance based on the touch. The detection result of the touch istransmitted to control section 150.

When sensing the touch of the object in the off-state, control section150 applies the voltage to liquid crystal layer 115 of lens 110.Thereby, the orientation of the liquid crystal material in liquidcrystal layer 115 changes, and the refractive index of liquid crystallayer 115 changes (on-state).

In the on-state, the refractive index of liquid crystal layer 115 andthe refractive index of each of first transparent substrate 111 andsecond transparent substrate 112 are different from each other. Hencethe lens effect attributable to liquid crystal layer 115 occurs in firstregion 1101. Therefore, the focal length (power) of first region 1101can be changed.

In the on-state, when the portion of housing 141 which corresponds todetection section 142 is touched by the object, the detection result ofthe touch is transmitted to control section 150 in the same manner asabove. When sensing the touch of the object in the on-state, controlsection 150 stops applying the voltage to liquid crystal layer 115.Thereby, the orientation of the liquid crystal material in liquidcrystal layer 115 returns to the state before the application of thevoltage, and the refractive index of liquid crystal layer 115 alsoreturns to the state before the application of the voltage (off-state).

As described above, in electronic glasses 100 according to the presentembodiment, a touch of the object is sensed and then the focal length offirst region 1101 in lens 110 can be switched.

(Effects)

In lens 110 of electronic glasses 100 according to the presentembodiment, mark M including information is formed in intermediate layer113 disposed between first transparent substrate 111 and secondtransparent substrate 112. Therefore, as compared with the conventionallens having a mark formed on the outer surface thereof, in lens 110according to the present embodiment, mark M is unlikely to disappear orbe tampered with.

Further, in the middle of the manufacturing process of lens 110, mark Mcan be formed in a layer to be intermediate layer 113. Therefore, ascompared with the case of forming mark M after manufacturing of lens110, even if mark M is failed to be formed adequately, it is possible tominimize the losses of the part and the material of lens 110. Forexample, when the process of forming mark M is performed before theprocess of disposing liquid crystal layer 115, even if mark M is failedto be formed adequately, it is possible to suppress the losses of thematerials such as the liquid crystal material and the adhesive.

In the above embodiments, the case has been described where one mark Mis formed on lens 110, but the lens according to the present inventionis not limited to this aspect. For example, a plurality of marks may beplaced on one or both of blank part 170 and lens 110.

In the above embodiments, the electronic glasses with the pair oftemples 140 having detection sections 142 have been described, but theeyewear according to the present invention are not limited to thisaspect. For example, one temple may be made up only of a housing.

In the above embodiments, lens 110 having first region 1101 where thefocal length can be changed by electric control has been described asthe electroactive region. However, the lens according to the presentinvention is not limited to this aspect.

For example, lens may have, as the electroactive region, a region wherea light transmittance can be changed by electric control. In this case,the intermediate layer has a light modulation layer containing anelectrochromic material, a guest-host liquid crystal material, and thelike. The light modulation layer can be disposed over the first regionand the second region.

The present embodiment as thus described is not limited to the structuredescribed above, but is applicable to a structure other than thestructure described above by being subjected to various modificationwithin a range not deviating from the gist of the invention. Further,the present embodiment can be performed in a combination with otherembodiments in a technically consistent range.

Summary of Present Embodiment

The lens, the lens blank, and the eyewear according Embodiment 4described above include the following aspects:

[First Aspect]

A first aspect of the lens according to Embodiment 4 above is a lenshaving an electroactive region where an optical characteristic changesby electric control, the lens being provided with: a first transparentsubstrate; a second transparent substrate disposed on the firsttransparent substrate; and an intermediate layer disposed between thefirst transparent substrate and the second transparent substrate andhaving a first transparent conductive layer disposed on the firsttransparent substrate side and a second transparent conductive layerdisposed on the second transparent substrate side. In the intermediatelayer, a mark including information is formed.

According to the lens of the first aspect, it is possible to provide alens for eyewear, a lens blank and eyewear having the lens, on which amark hardly disappears or is hardly tampered with.

[Second Aspect]

A lens according to a second aspect is the lens according to the firstaspect, in which the optical characteristic of the electroactive regionchanges by application of a voltage across the first transparentconductive layer and the second transparent conductive layer.

[Third Aspect]

A lens according to a third aspect is the lens according to the first orsecond aspect, in which a mark includes at least one of information onmanufacturing of the lens, information on a material for the lens,information on performance of the lens, information on structuralfeatures of the lens, information used at the time of sale of the lens,and information on transportation of the lens.

[Fourth Aspect]

A lens according to a fourth aspect is the lens according to any one ofthe first to third aspects, in which the mark is placed on the moreopposite side to a user of the lens than a middle point of theintermediate layer in a thickness direction of the lens.

[Fifth Aspect]

A lens according to a fifth aspect is the lens according to any one ofthe first to fourth aspects, in which the intermediate layer has a firstauxiliary electrode extending inward from the outer edge of lens and iselectrically connected to the first transparent conductive layer, and asecond auxiliary electrode extending inward from the outer edge of lensand is electrically connected to the second transparent conductivelayer.

[Sixth Aspect]

A lens according to a sixth aspect is the lens according to the fifthaspect, in which the first auxiliary electrode and the second auxiliaryelectrode are arranged so as to be adjacent to each other in a frontview of the lens, and at least a part of the mark is placed between thefirst auxiliary electrode and the second auxiliary electrode in thefront view of the lens.

[Seventh Aspect]

A lens according to a seventh aspect is the lens according to the fifthor sixth aspect, in which at least a part of the mark is placed in aregion with a distance equal to or shorter than 12 mm from a virtualline connecting between the tip part of the first auxiliary electrodeand the tip part of the second auxiliary electrode.

[Eighth Aspect]

A lens according to an eighth aspect is the lens according to any one ofthe fifth to seventh aspects, in which in the front view of the lens, atleast a part of the mark is placed in a region with a distance equal toor shorter than 19 mm from the one or both of the tip part of the firstauxiliary electrode and the tip part of the second auxiliary electrode.

[Ninth Aspect]

A lens according to a ninth aspect is the lens according to any one ofthe fifth to eighth aspects, in which in the front view of the lens, atleast a part of the mark is placed so as to overlap with one or both ofthe first auxiliary electrode and the second auxiliary electrode.

[Tenth Aspect]

A lens according to a tenth aspect is the lens according to any one ofthe first to ninth aspects, in which in the front view of the lens, atleast a part of the mark is placed in a region with a distance equal toor shorter than 24 mm from an electroactive region where a focal lengthcan be changed.

[Eleventh Aspect]

A lens according to an eleventh aspect is the lens according to any oneof the first to tenth aspects, in which the lens is a lens for eyewear,and when the lens is disposed in the frame for eyewear and in the frontview of the eyewear, the mark is placed so as to be adjacent to theelectroactive region where the focal length can be changed in thelaterally outer-side region of the eyewear.

[Twelfth Aspect]

A lens according to a twelfth aspect is the lens according to any one ofthe first to eleventh aspects, in which the mark is formed in one orboth of the first transparent conductive layer and the secondtransparent conductive layer by printing or engraving.

[Thirteenth Aspect]

A lens according to a thirteenth aspect is the lens according to theninth aspect, in which the mark is formed by printing or engraving onone or both of the first auxiliary electrode and the second auxiliaryelectrode.

[Fourteenth Aspect]

A lens according to a fourteenth aspect is the lens according to any oneof the first to thirteenth aspects, in which a conductive materialconstituting each of the first transparent conductive layer and thesecond transparent conductive layer contains ITO.

[Fifteenth Aspect]

A lens according to a fifteenth aspect is the lens according to any oneof the first to fourteenth aspects, in which the intermediate layerfurther has a liquid crystal layer disposed between the firsttransparent substrate and the second transparent substrate andcontaining a liquid crystal material, in a region corresponding to theelectroactive region where the focal length can be changed.

[Sixteenth Aspect]

Lens blank according to a sixteenth aspect is provided with: a lens; anda blank part formed together with the lens as a unit, in which the lensand the blank part each have a first transparent substrate, a secondtransparent substrate disposed on the first transparent substrate, andan intermediate layer disposed between the first transparent substrateand the second transparent and having a first transparent conductivelayer disposed on the first transparent substrate side and a secondtransparent conductive layer disposed on the second transparent side. Amark including information is formed in the intermediate layer, and themark is placed in a position of the intermediate layer which correspondsto one or both of the lens and the blank part.

[Seventeenth Aspect]

Eyewear according to a seventeenth aspect is provided with: the lensaccording to any one of the first to fifteenth aspects; a frame holdingthe lens; and a control section configured to control an opticalcharacteristic of the electroactive region of the lens by controlling avoltage across the first transparent conductive layer and the secondtransparent conductive layer.

This application claims priority to Japanese Application No. 2016-253581filed Dec. 27, 2016, Japanese Application No. 2016-253582 filed Dec. 27,2016, and Japanese Application No. 2017-037313 filed Feb. 28, 2017, andthe contents described in the specification, claims and drawings areincorporated herein by reference in their entirety.

INDUSTRIAL APPLICABILITY

A lens of the present invention can be used preferably as a lens foreyewear.

REFERENCE SIGNS LIST

-   10, 10 a, 10 b Electronic glasses (eyewear)-   12, 12 a Lens-   14, 14 a Lens-   16, 16 a Frame-   18 Liquid crystal (electroactive section, focal-length changing    section)-   22, 22 a Right-side rim (lens holder)-   24, 24 a Left-side rim (lens holder)-   200 Upper rim element-   201 First side rim element-   202 Second side rim element-   26 Bridge-   30 Right-side temple (temple)-   32 Left-side temple (temple)-   42 Flexible cable (external electrode)-   48, 50 Internal electrode-   48A, 50A Lower end of electrode-   60 Diffraction section (electroactive section, focal-length changing    section)-   68 Lens body-   72 Conductive rubber-   74 First fitting part (first region)-   76, 76 a to 76 f Second fitting part (second region)-   76A Front-side inclined surface-   76B Rear-side inclined surface-   78 Protruding part (exposed part)-   83, 83 a, 83 b Wire-   84, 84 a, 84 b, 84 c, 84 d, 84 e Wire fitting groove (groove part)-   85 a, 85 b, 85 c Protrusion-   86 Rubber placement groove (exposed part)-   87 Wire fitting notch-   VC1 Line passing through gravity center of blank body and extending    in lateral direction-   LC2 Diffraction-section center line (center line of electroactive    section and center line of focal-length changing section)-   C3 Gravity center of lens body-   VC3 Line passing through gravity center of lens body and extending    in lateral direction-   LC3 Line (center line) passing through gravity center of lens body    and extend in vertical direction-   100 Electronic glasses (eyewear)-   110, 110 a to 110 d Lens-   1101 First region (electroactive region)-   1102 Second region-   1103 Protrusion-   1104 Protruding strip-   111 First transparent substrate-   112 Second transparent substrate-   113 Intermediate layer-   114 first transparent conductive layer-   1141 First slit-   1142 Second slit-   115 Liquid crystal layer-   116 Second transparent conductive layer-   1161 Third slit-   1162 Fourth slit-   117 First auxiliary electrode-   118 Adhesive layer-   119 Second auxiliary electrode-   120 Frame-   130 Front-   131 Rim-   132 Bridge-   133 Nose pad-   140 Temple-   141 Housing-   142 Detection section-   150 Control section-   160 Power source-   170, 170 d Blank part-   180 Wiring-   2000, 2000 a to 2000 d Lens blank-   M, Ma to Md Mark

What is claimed is:
 1. A lens that includes an electroactive regionwhere an optical characteristic changes by electric control, the lenscomprising: a first transparent substrate; a second transparentsubstrate disposed facing the first transparent substrate; and anintermediate layer disposed between the first transparent substrate andthe second transparent substrate and including a mark includinginformation, wherein: the first transparent substrate is disposed on aposition closer to a user of the lens than the second transparentsubstrate in a state where the lens is in use; the intermediate layerincludes a liquid crystal layer in a position which corresponds to theelectroactive region; and the mark is placed on a position closer to thesecond transparent substrate than the liquid crystal layer in thethickness direction of lens.
 2. The lens according to claim 1, whereinthe mark includes at least one of information on manufacturing of thelens, information on a material for the lens, information on performanceof the lens, information on structural features of the lens, informationused at the time of sale of the lens, and information on transportationof the lens.
 3. The lens according to claim 1, wherein: the firsttransparent substrate is disposed on a position closer to a user of thelens than the second transparent substrate in a state where the lens isin use, and the mark is placed on a position closer to the secondtransparent substrate than the middle point of the intermediate layer inthe thickness direction of lens.
 4. The lens according to claim 1,wherein the mark is placed below a horizontal line passing through thecenter of gravity of the lens in the front view of lens.
 5. The lensaccording to claim 4, wherein the mark is placed on the outer side inthe width direction of the lens than a vertical line passing through thecenter of gravity of the lens in the front view of the lens.
 6. The lensaccording to claim 1, wherein: the intermediate layer includes a firstelectrode and a second electrode, the first electrode includes a firstauxiliary electrode which extends inward from the outer edge of lens,the second electrode includes a second auxiliary electrode which extendsinward from the outer edge of lens, the first auxiliary electrode andthe second auxiliary electrode are arranged so as to be adjacent to eachother in a front view of the lens, and at least a part of the mark isplaced between the first auxiliary electrode and the second auxiliaryelectrode in the front view of the lens.
 7. The lens according to claim1, wherein: the intermediate layer includes a first electrode and asecond electrode, the first electrode includes a first auxiliaryelectrode which extends inward from the outer edge of lens, the secondelectrode includes a second auxiliary electrode which extends inwardfrom the outer edge of lens, and at least a part of the mark is placedin a region with a distance equal to or shorter than 12 mm from avirtual line connecting between the tip part of the first auxiliaryelectrode and the tip part of the second auxiliary electrode.
 8. Thelens according to claim 1, wherein: the intermediate layer includes afirst electrode and a second electrode, the first electrode includes afirst auxiliary electrode which extends inward from the outer edge oflens, the second electrode includes a second auxiliary electrode whichextends inward from the outer edge of lens, and at least a part of themark is placed in a region with a distance equal to or shorter than 19mm from the one or both of the tip part of the first auxiliary electrodeand the tip part of the second auxiliary electrode.
 9. The lensaccording to claim 1, wherein: the intermediate layer includes a firstelectrode and a second electrode, the first electrode includes a firstauxiliary electrode which extends inward from the outer edge of lens,the second electrode includes a second auxiliary electrode which extendsinward from the outer edge of lens, and at least a part of the mark isplaced so as to overlap with one or both of the first auxiliaryelectrode and the second auxiliary electrode in the front view of lens.10. The lens according to claim 9, wherein the mark is formed byprinting or engraving on one or both of the first auxiliary electrodeand the second auxiliary electrode.
 11. The lens according to claim 1,wherein at least a part of the mark is placed in a region with adistance equal to or shorter than 24 mm from the electroactive region inthe front view of lens.
 12. The lens according to claim 1, wherein: thelens is a lens for eyewear and is incorporated in a frame includingtemple, and the mark is placed in a region between the electroactiveregion and the temple in the lens.
 13. The lens according to claim 1,wherein: the intermediate layer includes a first transparent conductivelayer disposed on the first transparent substrate side and a secondtransparent conductive layer disposed on the second transparentsubstrate side, and the mark is formed in one or both of the firsttransparent conductive layer and the second transparent conductive layerby printing or engraving.
 14. An eyewear comprising: the lens accordingto claim 1; a frame holding the lens; and a control section configuredto control an optical characteristic of the electroactive region of thelens by controlling a voltage applied to the electroactive region of thelens.
 15. A lens that includes an electroactive region where an opticalcharacteristic changes by electric control, the lens comprising: a firsttransparent substrate; a second transparent substrate disposed facingthe first transparent substrate; and an intermediate layer disposedbetween the first transparent substrate and the second transparentsubstrate and including a mark including information, wherein: theintermediate layer includes a first electrode and a second electrode,the first electrode includes a first auxiliary electrode which extendsinward from the outer edge of lens, the second electrode includes asecond auxiliary electrode which extends inward from the outer edge oflens, the first auxiliary electrode and the second auxiliary electrodeare arranged so as to be adjacent to each other in a front view of thelens, and at least a part of the mark is placed between the firstauxiliary electrode and the second auxiliary electrode in the front viewof the lens.
 16. A lens that includes an electroactive region where anoptical characteristic changes by electric control, the lens comprising:a first transparent substrate; a second transparent substrate disposedfacing the first transparent substrate; and an intermediate layerdisposed between the first transparent substrate and the secondtransparent substrate and including a mark including information,wherein: the intermediate layer includes a first electrode and a secondelectrode, the first electrode includes a first auxiliary electrodewhich extends inward from the outer edge of lens, the second electrodeincludes a second auxiliary electrode which extends inward from theouter edge of lens, and at least a part of the mark is placed so as tooverlap with one or both of the first auxiliary electrode and the secondauxiliary electrode in the front view of lens.